Monarch an Endangered Species: What You Can Do Right Now

This month, the International Union for Conservation of Nature (I.U.C.N.) added the Migratory Monarch Butterfly (Danaus plexippus plexippus) to its “Red List of Threatened Species”, classifying it as endangered.  Perhaps there is no better time than the present to have a look at the virtues of replacing areas of mowed and manicured grass with a wildflower garden or meadow that provides essential breeding and feeding habitat for Monarchs and hundreds of other species of animals.

Monarch on Common Milkweed Flower Cluster
A recently arrived Monarch visits a cluster of fragrant Common Milkweed flowers in the garden at the susquehannawildlife.net headquarters.  Milkweeds included among a wide variety of plants in a garden or meadow habitat can help local populations of Monarchs increase their numbers before the autumn flights to wintering grounds commence in the fall.  Female Monarchs lay their eggs on milkweed leaves, then, after hatching, the larvae (caterpillars) feed on them before pupating.

If you’re not quite sure about finally breaking the ties that bind you to the cult of lawn manicuring, then compare the attributes of a parcel maintained as mowed grass with those of a space planted as a wildflower garden or meadow.  In our example we’ve mixed native warm season grasses with the wildflowers and thrown in a couple of Eastern Red Cedars to create a more authentic early successional habitat.

Comparison of Mowed Grass to Wildflower Meadow
* Particularly when native warm-season grasses are included (root depth 6′-8′)

Still not ready to take the leap.  Think about this: once established, the wildflower planting can be maintained without the use of herbicides or insecticides.  There’ll be no pesticide residues leaching into the soil or running off during downpours.  Yes friends, it doesn’t matter whether you’re using a private well or a community system, a wildflower meadow is an asset to your water supply.  Not only is it free of man-made chemicals, but it also provides stormwater retention to recharge the aquifer by holding precipitation on site and guiding it into the ground.  Mowed grass on the other hand, particularly when situated on steep slopes or when the ground is frozen or dry, does little to stop or slow the sheet runoff that floods and pollutes streams during heavy rains.

What if I told you that for less than fifty bucks, you could start a wildflower garden covering 1,000 square feet of space?  That’s a nice plot 25′ x 40′ or a strip 10′ wide and 100′ long along a driveway, field margin, roadside, property line, swale, or stream.  All you need to do is cast seed evenly across bare soil in a sunny location and you’ll soon have a spectacular wildflower garden.  Here at the susquehannawildllife.net headquarters we don’t have that much space, so we just cast the seed along the margins of the driveway and around established trees and shrubs.  Look what we get for pennies a plant…

Wildflower Garden
Some of the wildflowers and warm-season grasses grown from scattered seed in the susquehannawildlife.net headquarters garden.

Here’s a closer look…

Lance-leaved Coreopsis
Lance-leaved Coreopsis (Coreopsis lanceolata), a perennial.
Black-eyed Susan
Black-eyed Susan, a biennial or short-lived perennial.
Black-eyed Susan "Gloriosa Daisy"
“Gloriosa Daisy”, a variety of Black-eyed Susan, a biennial or short-lived perennial.
Purple Coneflower
Purple Coneflower, an excellent perennial for pollinators.  The ripe seeds provide food for American Goldfinches.
Common Sunflower
A short variety of Common Sunflower, an annual and a source of free bird seed.
Common Sunflower
Another short variety of Common Sunflower, an annual.

All this and best of all, we never need to mow.

Around the garden, we’ve used a northeast wildflower mix from American Meadows.  It’s a blend of annuals and perennials that’s easy to grow.  On their website, you’ll find seeds for individual species as well as mixes and instructions for planting and maintaining your wildflower garden.  They even have a mix specifically formulated for hummingbirds and butterflies.

Annuals in bloom
When planted in spring and early summer, annuals included in a wildflower mix will provide vibrant color during the first year.  Many varieties will self-seed to supplement the display provided by biennials and perennials in subsequent years.
Wildflower Seed Mix
A northeast wildflower mix from American Meadows.  There are no fillers.  One pound of pure live seed easily plants 1,000 square feet.

Nothing does more to promote the spread and abundance of non-native plants, including invasive species, than repetitive mowing.  One of the big advantages of planting a wildflower garden or meadow is the opportunity to promote the growth of a community of diverse native plants on your property.  A single mowing is done only during the dormant season to reseed annuals and to maintain the meadow in an early successional stage—preventing reversion to forest.

For wildflower mixes containing native species, including ecotypes from locations in and near the Lower Susquehanna River Watershed, nobody beats Ernst Conservation Seeds of Meadville, Pennsylvania.  Their selection of grass and wildflower seed mixes could keep you planting new projects for a lifetime.  They craft blends for specific regions, states, physiographic provinces, habitats, soils, and uses.  Check out these examples of some of the scores of mixes offered at Ernst Conservation Seeds

      • Pipeline Mixes
      • Pasture, Grazing, and Hay Mixes
      • Cover Crops
      • Pondside Mixes
      • Warm-season Grass Mixes
      • Retention Basin Mixes
      • Wildlife Mixes
      • Pollinator Mixes
      • Wetland Mixes
      • Floodplain and Riparian Buffer Mixes
      • Rain Garden Mixes
      • Steep Slope Mixes
      • Solar Farm Mixes
      • Strip Mine Reclamation Mixes

We’ve used their “Showy Northeast Native Wildflower and Grass Mix” on streambank renewal projects with great success.  For Monarchs, we really recommend the “Butterfly and Hummingbird Garden Mix”.  It includes many of the species pictured above plus “Fort Indiantown Gap” Little Bluestem, a warm-season grass native to Lebanon County, Pennsylvania, and milkweeds (Asclepias), which are not included in their northeast native wildflower blends.  More than a dozen of the flowers and grasses currently included in this mix are derived from Pennsylvania ecotypes, so you can expect them to thrive in the Lower Susquehanna River Watershed.

Swamp Milkweed
Swamp Milkweed, a perennial species, is included in the Ernst Seed “Butterfly and Hummingbird Garden Mix”.  It is a favorite of female Monarchs seeking a location to deposit eggs.
Monarch Caterpillar feeding on Swamp Milkweed
A Monarch larva (caterpillar) feeding on Swamp Milkweed.
Butterfly Weed
Butterfly Weed (Asclepias tuberosa) is included in the Ernst Seed “Butterfly and Hummingbird Garden Mix”.  This perennial is also known as Butterfly Milkweed.
Tiger Swallowtails visiting Butterfly Weed
Eastern Tiger Swallowtails are among the dozens of species of pollinators that will visit Butterfly Weed.

In addition to the milkweeds, you’ll find these attractive plants included in Ernst Conservation Seed’s “Butterfly and Hummingbird Garden Mix”, as well as in some of their other blends.

Wild Bergamot
The perennial Wild Bergamot, also known as Bee Balm, is an excellent pollinator plant, and the tubular flowers are a favorite of hummingbirds.
Oxeye
Oxeye is adorned with showy clusters of sunflower-like blooms in mid-summer.  It is a perennial plant.
Plains Coreopsis
Plains Coreopsis (Coreopsis tinctoria), also known as Plains Tickseed, is a versatile annual that can survive occasional flooding as well as drought.
Gray-headed Coneflower
Gray-headed Coneflower (Ratibida pinnata), a tall perennial, is spectacular during its long flowering season.
Monarch on goldenrod.
Goldenrods are a favorite nectar plant for migrating Monarchs in autumn.  They seldom need to be sown into a wildflower garden; the seeds of local species usually arrive on the wind.  They are included in the “Butterfly and Hummingbird Garden Mix” from Ernst Conservation Seeds in low dose, just in case the wind doesn’t bring anything your way.
Partridge Pea
Is something missing from your seed mix?  You can purchase individual species from the selections available at American Meadows and Ernst Conservation Seeds.  Partridge Pea is a good native annual to add.  It is a host plant for the Cloudless Sulphur butterfly and hummingbirds will often visit the flowers.  It does really well in sandy soils.
Indiangrass in flower.
Indiangrass is a warm-season species that makes a great addition to any wildflower meadow mix.  Its deep roots make it resistant to drought and ideal for preventing erosion.

Why not give the Monarchs and other wildlife living around you a little help?  Plant a wildflower garden or meadow.  It’s so easy, a child can do it.

Planting a riparian buffer with wildflowers and warm-season grasses
Volunteers sow a riparian buffer on a recontoured stream bank using wildflower and warm-season grass seed blended uniformly with sand.  By casting the sand/seed mixture evenly over the planting site, participants can visually assure that seed has been distributed according to the space calculations.
Riparian Buffer of wildflowers
The same seeded site less than four months later.
Monarch Pupa
A Monarch pupa from which the adult butterfly will emerge.

Photo of the Day

Leafcutter Bee Visiting Wild Bergamot (Monarda fistulosa)
A Leafcutter Bee (Megachile species) visits the blossoms of a Wild Bergamot (Monarda fistulosa), a native wildflower also known as Bee Balm or Horsemint.  Like Mason Bees (Osmia species), leafcutters will readily nest in the tubular cavities provided inside man-made bee houses.  As their names suggest, Mason Bees use mud to construct and seal the cells for their eggs while leafcutters harvest leaves for the task.  Female Leafcutter Bees, including this individual, can be recognized by the accumulation of pollen carried on the underside of their abdomen.  Within each nest cell, a female will lay an egg atop a supply of pollen and nectar.  These provisions will nourish the larva through development and transformation into an adult.

Photo of the Day

Buttonbush flower cluster
Is it the latest image from NASA’s new Webb Space Telescope?  Nope, it’s the globular flower cluster of the Buttonbush, a native shrub species found throughout the Lower Susquehanna River Watershed.  Buttonbush thrives in wet soil and seldom grows taller than 10 feet in height.  Try it along stream banks, in stormwater retention basins, and in rain gardens fed by surface runoff or the outflow from your downspouts.

The Mexican Cigar

You’ve heard and read it before—native plants do the best job of providing sustenance for our indigenous wildlife.  Let’s say you have a desire to attract hummingbirds to your property and you want to do it without putting up feeders.  Well, you’ll need native plants that provide tubular flowers from which these hovering little birds can extract nectar.  Place enough of them in conspicuous locations and you’ll eventually see hummingbirds visiting during the summer months.  If you have a large trellis, pole, or fence, you might plant a Trumpet Vine, also known as Trumpet Creeper.  They become adorned with an abundance of big red-orange tubular flowers that our Ruby-throated Hummingbirds just can’t resist.  For consistently bringing hummingbirds to the garden, Trumpet Vine may be the best of the various plants native to the Mid-Atlantic States.

Trumpet Vine
The showy bloom clusters of Trumpet Vine are irresistible to Ruby-throated Hummingbirds.

There is a plant, not particularly native to our area but native to the continent, that even in the presence of Trumpet Vine, Pickerelweed, Partridge Pea, and other reliable hummingbird lures will outperform them all.  It’s called Mexican Cigar (Cuphea ignea) or Firecracker Plant.  Its red and yellow tubular flowers look like a little cigar, often with a whitish ash at the tip.  Its native range includes some of the Ruby-throated Hummingbird’s migration routes and wintering grounds in Mexico and the Caribbean Islands, where they certainly are familiar with it.

This morning in the susquehannawildlife.net headquarters garden, the Ruby-throated Hummingbird seen in the following set of images extracted nectar from the Mexican Cigar blossoms exclusively.  It ignored the masses of showy Trumpet Vine blooms and other flowers nearby—as the hummers that stop by usually do when Cuphea is offered.

Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea)Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea) Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea)Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea)Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea)Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea) Some garden centers still have Mexican Cigar plants available.  You can grow them in pots or baskets, then bring them inside before frost to treat them as a house plant through the winter.  Give the plants a good trim sometime before placing them outside when the weather warms in May.  You’ll soon have Ruby-throated Hummingbirds visiting again for the summer.

Ruby-throated Hummingbird and Mexican Cigar (Cuphea ignea)
  

Blooming in Early July: Great Rhododendron

With the gasoline and gunpowder gang’s biggest holiday of the year now upon us, wouldn’t it be nice to get away from the noise and the enduring adolescence for just a little while to see something spectacular that isn’t exploding or on fire?  Well, here’s a suggestion: head for the hills to check out the flowers of our native rhododendron, the Great Rhododendron (Rhododendron maximum), also known as Rosebay.

Great Rhododendron
The Great Rhododendron is an evergreen shrub found growing in the forest understory on slopes with consistently moist (mesic) soils.  The large, thick leaves make it easy to identify.  During really cold weather, they may droop and curl, but they still remain green and attached to the plant.

Thickets composed of our native heathers/heaths (Ericaceae) including Great Rhododendron, Mountain Laurel, and Pinxter Flower (Rhododendron periclymenoides), particularly when growing in association with Eastern Hemlock and/or Eastern White Pine, provide critical winter shelter for forest wildlife.  The flowers of native heathers/heaths attract bees and other pollinating insects and those of the deciduous Pinxter Flower, which blooms in May, are a favorite of butterflies and Ruby-throated Hummingbirds.

Pinxter Flower in bloom
A close relative of the Great Rhododendron is the Pinxter Flower, also known as the Pink Azalea.

Forests with understories that include Great Rhododendrons do not respond well to logging.  Although many Great Rhododendrons regenerate after cutting, the loss of consistent moisture levels in the soil due to the absence of a forest canopy during the sunny summertime can, over time, decimate an entire population of plants.  In addition, few rhododendrons are produced by seed, even under optimal conditions.  Great Rhododendron seeds and seedlings are very sensitive to the physical composition of forest substrate and its moisture content during both germination and growth.  A lack of humus, the damp organic matter in soil, nullifies the chances of successful recolonization of a rhododendron understory by seed.  In locations where moisture levels are adequate for their survival and regeneration after logging, impenetrable Great Rhododendron thickets will sometimes come to dominate a site.  These monocultures can, at least in the short term, cause problems for foresters by interrupting the cycle of succession and excluding the reestablishment of native trees.  In the case of forests harboring stands of Great Rhododendron, it can take a long time for a balanced ecological state to return following a disturbance as significant as logging.

Birds of Conewago Falls in the Lower Susquehanna River Watershed: Ruffed Grouse
Ruffed Grouse (Bonasa umbellus) may be particularly sensitive to the loss of winter shelter and travel lanes provided by thickets of Great Rhododendron and other members of the heather/heath family.  (Vintage 35 mm image)

In the lower Susquehanna region, the Great Rhododendron blooms from late June through the middle of July, much later than the ornamental rhododendrons and azaleas found in our gardens.   Set against a backdrop of deep green foliage, the enormous clusters of white flowers are hard to miss.

Great Rhododendron Flower Cluster
Great Rhododendrons sport an attractive blossom cluster.  The colors of the flower, especially the markings found only on the uppermost petal, guide pollinators to the stamens (male organs) and pistil (female organ).
Bumble Bee Pollinating a Great Rhododendron Flower
To this Bumble Bee (Bombus species), the yellowish spots on the uppermost petal of the Great Rhododendron may appear to be clumps of pollen and are thus an irresistible lure.  

In the Lower Susquehanna River Watershed, there are but a few remaining stands of Great Rhododendron.  One of the most extensive populations is in the Ridge and Valley Province on the north side of Second Mountain along Swatara Creek near Ravine (just off Interstate 81) in Schuylkill County, Pennsylvania.  Smaller groves are found in the Piedmont Province in the resort town of Mount Gretna in Lebanon County and in stream ravines along the lower river gorge at the Lancaster Conservancy’s Ferncliff and Wissler’s Run Preserves.  Go have a look.  You’ll be glad you did.

Great Rhododendron along Route 125 near Ravine
Great Rhododendron along Route 125 along the base of the north slope of Second Mountain north of Ravine, Schuylkill County, Pennsylvania.
Great Rhododendron along Swatara Creek
Great Rhododendrons beginning to bloom during the second week of July along Swatara Creek north of Ravine, Schuylkill County, Pennsylvania.  Note how acid mine drainage continues to stain the rocks (and pollute the water) in the upper reaches of this tributary of the lower Susquehanna.

Early May Migration

National Weather Service radar showed a sizeable nocturnal flight of migrating birds early this morning.  Let’s go for a short stroll and see what’s around.

Radar returns from State College, Pennsylvania, display several bands of light rain and a massive flight of migrating birds.  (NOAA/National Weather Service image)
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Gray Catbird
After coming in on an overnight flight, Gray Catbirds were numerous at dawn this morning.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Black-and-white Warbler
Masses of Neotropical migrants are just beginning to arrive.  This Black-and-white Warbler was found feeding on insects in a Green Ash tree that, so far, has survived Emerald Ash Borer (Agrilus planipennis) infestation.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Veery
The Veery is a Neotropical thrush that nests in understory vegetation on forested slopes in the Lower Susquehanna River Watershed.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Orchard Oriole
Orchard Orioles are here.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Baltimore Oriole
And Baltimore Orioles are here too.  Vibrant colors like these are what many observers find so wonderful about many of the Neotropical species.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Double-crested Cormorants
Not all migrants move at night.  While you’re out and about, keep an eye on the sky for diurnal fliers like these migrating Double-crested Cormorants, seen this morning a full ten miles east of the river.
Birds of Conewago Falls in the Lower Susquehanna River Watershed: Carolina Wren
While many birds are still working their way north to their breeding grounds, resident species like this Carolina Wren are already feeding young.  This one has collected a spider for its nestlings.

Times Are Tough

Rising prices, an exhausted workforce, political polarization, and pandemic fatigue—times are tough.  Product shortages have the consumer culture in a near panic.  Some say the future just isn’t what it used to be.

Well, Uncle Tyler Dyer reminds us that things could be worse.  He shares with us this observation, “Man, as long as people are spending money poisoning the weeds on their lawns instead of eating them, things aren’t that bad.”

Uncle Ty is particularly fond of the Common Dandelion (Taraxacum officinale), “Check it out.  Roasted dandelion roots can make a coffee substitute, the blossoms a wine, and the leaves used to create my favorites, nutrient-dense salads or green vegetable dishes.”

The Common Dandelion is despised by many as a “weed”.  To others it is a beautiful flowering plant that happens to be quite edible.  Native to Europe and Asia, North American varieties of Common Dandelion are an escape from cultivation, originally imported as a food crop.  Uncle Ty’s great-grandparents never would have dreamed of killing them with herbicides instead of harvesting them.
Uncle Ty Dyer’s lunch, fresh dandelion greens and hot bacon dressing.

So have a homegrown salad and remember, maybe things aren’t that bad after all.

Five Best Values for Feeding Birds

Despite being located in an urbanized downtown setting, blustery weather in recent days has inspired a wonderful variety of small birds to visit the garden here at the susquehannawildlife.net headquarters to feed and refresh.  For those among you who may enjoy an opportunity to see an interesting variety of native birds living around your place, we’ve assembled a list of our five favorite foods for wild birds.

American Goldfinches in drab winter (basic) plumage visit the trickle of water entering the headquarters pond to bathe and drink.  In addition to offering the foods animals need to survive, a source of clean water is an excellent way to attract wildlife to your property.

The selections on our list are foods that provide supplemental nutrition and/or energy for indigenous species, mostly songbirds, without sustaining your neighborhood’s non-native European Starlings and House Sparrows, mooching Eastern Gray Squirrels, or flock of ecologically destructive hand-fed waterfowl.  We’ve included foods that aren’t necessarily the cheapest but are instead those that are the best value when offered properly.

Bread, “bargain” seed mixes, and cracked corn can attract and sustain large numbers of House Sparrows and European Starlings.  Both are non-native species that compete mercilessly with indigenous birds including bluebirds for food and nesting sites.  Though found favorable for feeding Northern Cardinals without attracting squirrels, the expensive safflower seed seen here is another favorite of these aggressive House Sparrows.  Ever wasteful, they “shovel” seed out of feeders while searching for the prime morsels from which they can easily remove the hulls.  Trying not to feed them is an ongoing challenge, so we don’t offer these aforementioned foods to our avian guests.

Number 5

Raw Beef Suet

In addition to rendered beef suet, manufactured suet cakes usually contain seeds, cracked corn, peanuts, and other ingredients that attract European Starlings, House Sparrows, and squirrels to the feeder, often excluding woodpeckers and other native species from the fare.  Instead, we provide raw beef suet.

Because it is unrendered and can turn rancid, raw beef suet is strictly a food to be offered in cold weather.   It is a favorite of woodpeckers, nuthatches, and many other species.  Ask for it at your local meat counter, where it is generally inexpensive.

Raw beef suet is fat removed from areas surrounding the kidneys on a beef steer.  To avoid spoiling, offer it only in the winter months, particularly if birds are slow to consume the amount placed for them.  If temperatures are above freezing, it’s important to replace uneaten food frequently.  The piece seen here on the left was stored in the freezer for almost a year while the rancid piece to the right was stored in a refrigerator at about 40 degrees Fahrenheit for just two months.  You can render raw beef suet and make your own cakes by melting it down and pouring it into a form such as cupcake tin.  But do it outdoors or you’ll be living alone for a while.
A female Downy Woodpecker feeds on raw beef suet stuffed into holes drilled into a vertically hanging log.  Because they can’t be cleaned, log feeders should be discarded after one season.  Wire cage feeders though, can usually be scrubbed, disinfected, dried, and reused.
Pesky European Starlings might visit a raw beef suet feeder but won’t usually linger unless other foods to their liking are available nearby.
This male Downy Woodpecker has no trouble feeding on raw beef suet packed into holes drilled into the underside of this horizontally hanging log.  Starlings don’t particularly care to feed this way.
Unusual visitors like a Brown Creeper are more likely to stop by at a suet feeder when it isn’t crowded by raucous starlings, House Sparrows, and squirrels.   This one surprised us just this morning.
Below the feeders, scraps of suet that fall to the ground are readily picked up, usually by ground-feeding birds.  In this instance, a male Eastern Bluebird saw a chunk break loose and pounced on it with haste.

Number 4

Niger (“Thistle”) Seed

Niger seed, also known as nyjer or nyger, is derived from the sunflower-like plant Guizotia abyssinica, a native of Ethiopia.  By the pound, niger seed is usually the most expensive of the bird seeds regularly sold in retail outlets.  Nevertheless, it is a good value when offered in a tube or wire mesh feeder that prevents House Sparrows and other species from quickly “shoveling” it to the ground.  European starlings and squirrels don’t bother with niger seed at all.

Niger seed must be kept dry.  Mold will quickly make niger seed inedible if it gets wet, so avoid using “thistle socks” as feeders.  A dome or other protective covering above a tube or wire mesh feeder reduces the frequency with which feeders must be cleaned and moist seed discarded.  Remember, keep it fresh and keep it dry!

Niger (“thistle”) seed is very small, so it is offered in specialized feeders to prevent seed from spilling out of oversize holes as waste.
An American Goldfinch in winter plumage feeding on niger seed from a wire mesh feeder.  By April, goldfinches are molting into spectacular breeding feathers.  Niger seed can be offered year-round to keep them visiting your garden while they are at maximum magnificence.
American Goldfinches in August.  This tube feeder is designed specifically for goldfinches, birds that have no difficulty hanging upside down to grab niger seed from small feeding ports.
During invasion years, visiting Pine Siskins favor niger seed at feeding stations.
Like goldfinches, Pine Siskins are quite comfortable feeding upside down on specialized tubes with perches positioned above the seed ports.  Seeds dropped to the ground are readily picked up by ground-feeding birds including Mourning Doves and Dark-eyed Juncos.  Periodically, uneaten niger seed should be swept up and discarded.

Number 3

Striped Sunflower Seed

Striped sunflower seed, also known as grey-striped sunflower seed, is harvested from a cultivar of the Common Sunflower (Helianthus annuus), the same tall garden plant with a massive bloom that you grew as a kid.  The Common Sunflower is indigenous to areas west of the Mississippi River and its seeds are readily eaten by many native species of birds including jays, finches, and grosbeaks.  The husks are harder to crack than those of black oil sunflower seed, so House Sparrows consume less, particularly when it is offered in a feeder that prevents “shoveling”.   For obvious reasons, a squirrel-proof or squirrel-resistant feeder should be used for striped sunflower seed.

Striped sunflower seed.
A male House Finch and a Carolina Chickadee pluck striped sunflower seeds from a squirrel-resistant powder-coated metal-mesh tube feeder.
An American Goldfinch in winter plumage finds striped sunflower seeds irresistible, even with niger seed being offered in an adjacent feeder.
A Tufted Titmouse visits a feeder stocked with striped sunflower seeds.
Northern Cardinals readily feed on striped sunflower seeds, especially those that fall from our metal-mesh tube feeders.
An Eastern Gray Squirrel (Sciurus carolinensis) has no choice but to be satisfied with striped sunflower seeds that spill from our wire-mesh tube feeders.

Number 2

Mealworms

Mealworms are the commercially produced larvae of the beetle Tenebrio molitor.  Dried or live mealworms are a marvelous supplement to the diets of numerous birds that might not otherwise visit your garden.  Woodpeckers, titmice, wrens, mockingbirds, warblers, and bluebirds are among the species savoring protein-rich mealworms.  The trick is to offer them without European Starlings noticing or having access to them because European Starlings you see, go crazy over a meal of mealworms.

Dried mealworms can be offered in a cup or on a tray feeder.  Live mealworms need to be contained in a steep-sided dish, so they don’t crawl away.  Unless you’re really lucky, you’ll probably have to place your serving vessel of mealworms inside some type of enclosure to exclude European Starlings.
A male Eastern Bluebird tossing and grabbing a dried mealworm.
A female Eastern Bluebird with a dried mealworm.
A pair of Eastern Bluebirds.  The value of mealworms is self-evident: you get to have bluebirds around.

 

To foil European Starlings, we assembled this homemade mealworm feeder from miscellaneous parts. The bluebirds took right to it.
It frustrates the starlings enough to discourage them from sticking around for long.
If you’re offering dried mealworms, a source of clean water must be available nearby so that the bluebirds and other guests at your feeder don’t become dehydrated.

Number 1

Food-producing Native Shrubs and Trees

The best value for feeding birds and other wildlife in your garden is to plant food-producing native plants, particularly shrubs and trees.  After an initial investment, they can provide food, cover, and roosting sites year after year.  In addition, you’ll have a more complete food chain on a property populated by native plants and all the associated life forms they support (insects, spiders, etc.).

In your garden, a Northern Mockingbird may defend a food supply like these Common Winterberry fruits as its sole means of sustenance for an entire winter season.  Having an abundance of plantings assures that in your cache there’s plenty to eat for this and other species.
The American Goldfinches currently spending the winter at our headquarters are visiting the feeders for niger and striped sunflower seeds, but the bulk of their diet consists of tiny seeds from the cones on our Eastern Hemlock trees.  At night, birds obtain shelter from the weather by roosting in this clump of evergreens.
While the Eastern Bluebirds visiting the susquehannawildlife.net headquarters are fond of mealworms, the bulk of their diet here consists of these Common Winterberry fruits and the berries on our American Holly trees.
Cedar Waxwings are readily attracted to red berries including Common Winterberry fruit.
Migrating American Robins visit the headquarters garden in late winter each year to devour berries before continuing their journey to the north.

Your local County Conservation District is having its annual spring tree sale soon.  They have a wide selection to choose from each year and the plants are inexpensive.  They offer everything from evergreens and oaks to grasses and flowers.  You can afford to scrap the lawn and revegetate your whole property at these prices—no kidding, we did it.  You need to preorder for pickup in the spring.  To order, check their websites now or give them a call.  These food-producing native shrubs and trees are by far the best bird feeding value that you’re likely to find, so don’t let this year’s sales pass you by!

Photo of the Day

A Pileated Woodpecker devours the dark blue berries of a Black Gum (Nyssa sylvatica). The Black Gum, also known as the Black Tupelo, Sour Gum, and Pepperidge, sports crimson leaves in the fall to attract birds to its fruit, thus assuring distribution of its seeds.  In 2021, the fruit is so abundant that it has outlasted the foliage, much to the delight of resident and migrating birds.

Photo of the Day

A migrating Monarch butterfly takes a break to feed on nectar from the blooms of a Frost Aster (Symphyotrichum pilosum), a common autumn wildflower also known as Heath Aster.

Blooming Now in the Lower Susquehanna Region: Mountain Laurel

Mountain Laurel (Kalmia latifolia), designated as Pennsylvania’s state flower, is a native evergreen shrub of forests situated on dry rocky slopes with acidic soils.  As the common name implies, we think of it mostly as a plant of the mountainous regions—those areas of the Susquehanna watershed north of Harrisburg.  It is indeed symbolic of Appalachian forests.  But Mountain Laurel can also be found to the south of the capital city in forested highlands of the Piedmont.  There, currently, it happens to be in full bloom.  Let’s put on a pair of sturdy shoes and take a walk in the Hellam Hills of eastern York County at Rocky Ridge County Park to have a look.

The showy flower clusters of blooming Mountain Laurel are conspicuous throughout Rocky Ridge County Park right now.
Mountain Laurel flowering in the utility right-of-way south of the main parking area at Rocky Ridge…
…and to the north of the parking area at the hawk-watch platform.
Strolling a forest trail, particularly west of the utility right-of-way, can take you on a path through a thicket of flowering Mountain Laurel.
The majority of Mountain Laurels one might encounter will sport white flowers.
Others vary, exhibiting shades of spectacular pink.
Look closely and you’ll see flowers with curled filaments on some of the stamens.  When a bee or other insect makes contact, they spring into an extended position to assure pollen transfer to the visiting pollinator.
Absolutely spectacular.

Rain or shine, do get out and have a look at the blooming Mountain Laurel.

More than a Mint Dish

On a snowy winter day, it sure is nice to see some new visitors at a backyard feeding station.  Here at the susquehannawildlife.net headquarters, American Robins have arrived to partake of the offerings.

American Robins feed on peanut hearts and chopped apples.

For this flock of robins, which numbered in excess of 150 individuals, the contents of this tray were a mere garnish to the meal that would sustain them through 72 hours of stormy weather.  The main course was the supply of ripe berries on shrubs and trees in the headquarters garden.

Their first choice—the bright red fruits of the Common Winterberry.

American Robins strip the fruits from a Common Winterberry.
Eat fast or lose your turn.
Irresistible crimson delights.
Cedar Waxwings get their share too.
Robins will linger until nightfall to feed on winterberries.

After cleaning off the winterberry shrubs, other fruits became part of the three-day-long feast.

Robins eating Highbush Cranberry (Viburnum opulus) fruits.
The blue-gray berries of junipers are attractive to robins, waxwings, and bluebirds.
The American Holly (Ilex opaca) is a favorite of berry-loving birds.  Its evergreen foliage provides cover and roosting sites for wintering birds.

Wouldn’t it be great to see these colorful birds in your garden each winter?  You can, you know.  Won’t you consider adding plantings of native trees and shrubs to your property this spring?  Here at the susquehannawildlife.com headquarters we mow no lawn; the lawn is gone.  Mixing evergreens and fruit-producing shrubs with native warm-season grasses and flowering plants has created a wildlife oasis absent of that dirty habit of mowing and blowing.

You can find many of the plants seen here at your local garden center.  Take a chunk out of your lawn by paying them a visit this spring.

Want a great deal?  Many of the County Conservation District offices in the lower Susquehanna region are having their annual spring tree sales right now.  Over the years, we obtained many of our evergreens and berry-producing shrubs from these sales for less than two dollars each.  At that price you can blanket that stream bank or wet spot in the yard with winterberries and mow it no more!  The deadlines for orders are quickly approaching, so act today—literally, act today.  Visit your County Conservation District’s website for details including selections, prices, order deadlines, and pickup dates and locations.

Evergreens like this Eastern Hemlock (Tsuga canadensis) are essential to the survival of many species of wintering birds.  Plant evergreens in clumps, the bigger the better, to provide birds with thermal protection against the cold winds of winter nights.
County Conservation District Tree Sales offer bare root evergreens like this Eastern White Pine (Pinus strobus) in packs of five or ten.  Buy a bunch.  Spend this year’s lawn treatment money on them.  Then, get them planted immediately after pickup in the spring and in a few years you’ll have a nice grove of evergreens for wildlife habitat, a wind break, or a privacy screen.
Groves of mixed evergreens among deciduous woods, grasslands, farmlands, or suburbs are ideal cover for wintering wildlife.  These stands attract many species of migrating and nesting birds as well.  Seen here, left to right, are Eastern White Pine, Norway Spruce (Picea abies), and Eastern Red Cedar.  Though not a native species, the Norway Spruce is frequently used for conservation and ornamental plantings in the northeastern United States due to its appealing attributes and lack of invasive characteristics.
Feeding wildlife is great fun.  But remember, if you’re running a hotel for animals, you’ve got to offer more than an after-dinner mint to your tired and hungry guests.  Let’s get planting!

County Conservation District Tree Sales

Consult each County Conservation District’s Tree Sale web page for ordering info, pickup locations, and changes to these dates and times.

Cumberland County Conservation District Tree Seedling Sale—deadline for prepaid orders Tuesday, March 30, 2021.  Pickup 1 P.M. to 5 P.M., Thursday, April 22, 2021, and 8 A.M. to 2 P.M., Friday, April 23, 2021.  https://www.ccpa.net/4636/Tree-Seedling-Sale

Lancaster County Conservation District Tree Sale—deadline for prepaid orders (hand-delivered to drop box) 5 P.M., Friday, March 5, 2021.  Pickup 8 A.M. to 5 P.M., Thursday, April 15, 2021.  https://www.lancasterconservation.org/tree-sale/

Lebanon County Conservation District Tree Sale—deadline for prepaid orders  Thursday, March 11, 2021.  Pickup 9 A.M. to 6 P.M., Friday, May 7, 2021.  https://www.lccd.org/2021-tree-sale/

Perry County Conservation District Tree Sale—deadline for prepaid orders Wednesday, March 24, 2021.  Pickup 10 A.M. to 6 P.M., Thursday, April 8, 2021.  www.perrycd.org/Documents/2021 Tree Sale Flyer LEGAL SIZE.pdf

York County Conservation District Seedling Sale—deadline for prepaid orders Monday, March 15, 2021.  Pickup 10 A.M. to 6 P.M., Thursday, April 15, 2021.  https://www.yorkccd.org/events/2021-seedling-sale

October Transition

Thoughts of October in the Lower Susquehanna River Watershed bring to mind scenes of brilliant fall foliage adorning wooded hillsides and stream courses, frosty mornings bringing an end to the growing season, and geese and other birds flying south for the winter.

The autumn migration of birds spans a period equaling nearly half the calendar year.  Shorebirds and Neotropical perching birds begin moving through as early as late July, just as daylight hours begin decreasing during the weeks following their peak at summer solstice in late June.  During the darkest days of the year, those surrounding winter solstice in late December, the last of the southbound migrants, including some hawks, eagles, waterfowl, and gulls, may still be on the move.

The Rough-legged Hawk (Buteo lagopus), a rodent-eating raptor of tundra, grassland, and marsh, is rare as a migrant and winter resident in the lower Susquehanna valley.  It may arrive as late as January, if at all.

During October, there is a distinct change in the list of species an observer might find migrating through the lower Susquehanna valley.  Reduced hours of daylight and plunges in temperatures—particularly frost and freeze events—impact the food sources available to birds.  It is during October that we say goodbye to the Neotropical migrants and hello to those more hardy species that spend their winters in temperate climates like ours.

During several of the first days of October, two hundred Chimney Swifts remained in this roost until temperatures warmed from the low forties at daybreak to the upper fifties at mid-morning; then, at last, the flock ventured out in search of flying insects.  When a population of birds loses its food supply or is unable to access it, that population must relocate or perish.  Like other insectivorous birds, these swifts must move to warmer climes to be assured a sustained supply of the flying bugs they need to survive.  Due to their specialized food source, they can be considered “specialist” feeders in comparison to species with more varied diets, the “generalists”.  After returning to this chimney every evening for nearly two months, the swifts departed this roost on October 5 and did not return.
A Northern Parula lingers as an October migrant along the Susquehanna.  This and other specialist feeders that survive almost entirely on insects found in the forest canopy are largely south of the Susquehanna watershed by the second week of October.
The Blackpoll Warbler is among the last of the insectivorous Neotropical warblers to pass through the riparian forests of the lower Susquehanna valley each fall.  Through at least mid-October, it is regularly seen searching for crawling insects and larvae among the foliage and bark of Northern Hackberry (Celtis occidentalis) trees near Conewago Falls.  Most other warblers, particularly those that feed largely upon flying insects, are, by then, already gone.
The Blue-headed Vireo, another insectivore, is the last of the vireo species to pass through the valley.  They linger only as long as there are leaves on the trees in which they feed.
Brown Creepers begin arriving in early October.  They are specialist feeders, well-adapted to finding insect larvae and other invertebrates among the ridges and peeling bark of trees like this hackberry, even through the winter months.
Ruby-crowned Kinglets can be abundant migrants in October.  They will often behave like cute little flycatchers, but quickly transition to picking insects and other invertebrates from foliage and bark as the weather turns frosty.  Some may spend the winter here, particularly in the vicinity of stands of pines, which provide cover and some thermal protection during storms and bitter cold.
Beginning in early October, Golden-crowned Kinglets can be seen searching the forest wood for tiny invertebrates.  They are the most commonly encountered kinglet in winter.
The Yellow-bellied Sapsucker, a woodpecker, is an October migrant that specializes in attracting small insects to tiny seeps of sap it creates by punching horizontal rows of shallow holes through the tree bark.  Some remain for winter.
The Yellow-rumped Warbler arrives in force during October.  It is the most likely of the warblers to be found here in winter.  Yellow-rumped Warblers are generalists, feeding upon insects during the warmer months, but able to survive on berries and other foods in late fall and winter.  Wild foods like these Poison Ivy berries are crucial for the survival of this and many other generalists.
American Robins are most familiar as hunters of earthworms on the suburban lawn, but they are generalist feeders that rely upon fruits like these Eastern Red Cedar (Juniperus virginiana) berries during their southbound migration in late October and early November each year.  Robins remain for the winter in areas of the lower Susquehanna valley with ample berries for food and groves of mature pines for roosting.
Like other brown woodland thrushes, the Hermit Thrush (Catharus guttatus) is commonly seen scratching through organic matter on the moist forest floor in search of invertebrates.  Unlike the other species, it is a cold-hardy generalist feeder, often seen eating berries during the southbound October migration.  Small numbers of Hermit Thrushes spend the winter in the lower Susquehanna valley, particularly in habitats with a mix of wild foods.
Due to their feeding behavior, Cedar Waxwings can easily be mistaken for flycatchers during the nesting season, but by October they’ve transitioned to voracious consumers of small wild fruits.  During the remainder of the year, flocks of waxwings wander widely in search of foods like this Fox Grape (Vitis labrusca).  An abundance of cedar, holly, Poison Ivy, hackberry, bittersweet , hawthorn, wild grape, and other berries is essential to their survival during the colder months.
Red-breasted Nuthatches have moved south in large numbers during the fall of 2020.  They were particularly common in the lower Susquehanna region during  mid-October.  Red-breasted Nuthatches can feed on invertebrates during warm weather, but get forced south from Canada in droves when the cone crops on coniferous trees fail to provide an adequate supply of seeds for the colder fall and winter seasons.  In the absence of wild foods, these generalists will visit feeding stations stocked with suet and other provisions.
Purple Finches (Haemorhous purpureus) were unusually common as October migrants in 2020.  They are often considered seed eaters during cold weather, but will readily consume small fruits like these berries on an invasive Mile-a-minute Weed (Persicaria perfoliata) vine.  Purple Finches are quite fond of sunflower seeds at feeding stations, but often shy away if aggressive House Sparrows or House Finches are present.

The need for food and cover is critical for the survival of wildlife during the colder months.  If you are a property steward, think about providing places for wildlife in the landscape.  Mow less.  Plant trees, particularly evergreens.  Thickets are good—plant or protect fruit-bearing vines and shrubs, and allow herbaceous native plants to flower and produce seed.  And if you’re putting out provisions for songbirds, keep the feeders clean.  Remember, even small yards and gardens can provide a life-saving oasis for migrating and wintering birds.  With a larger parcel of land, you can do even more.

GOT BERRIES?  Common Winterbery (Ilex verticillata) is a native deciduous holly that looks its best in the winter, especially with snow on the ground.  It’s slow-growing, and never needs pruning.  Birds including bluebirds love the berries and you can plant it in wet ground, even along a stream, in a stormwater basin, or in a rain garden where your downspouts discharge.  Because it’s a holly, you’ll need to plant a male and a female to get the berries.  Full sun produces the best crop.  Fall is a great time to plant, and many garden centers that sell holiday greenery still have winterberry shrubs for sale in November and December.  Put a clump of these beauties in your landscape.  Gorgeous!

Get Away From It All

For those of you who dare to shed that filthy contaminated rag you’ve been told to breathe through so that you might instead get out and enjoy some clean air in a cherished place of solitude, here’s what’s around—go have a look.

Northern Flickers have arrived.  Look for them anywhere there are mature trees.  Despite the fact that flickers are woodpeckers, they often feed on the ground.  You’ll notice the white rump and yellow wing linings when they fly away.
The tiny Chipping Sparrow frequently nests in small trees in suburban gardens.  Lay off the lawn treatments to assure their success.
Field Sparrows (Spizella fusilla) are a breeding species in abandoned fields where successional growth is underway.
White-throated Sparrows spend the winter in the lower Susquehanna valley.  Their numbers are increasing now as waves of migrants pass through on their way north.
Northbound flocks of Rusty Blackbirds (Euphagus carolinus) are currently found feeding in forest swamps along the Susquehanna.  Their noisy calls sound like a chorus of squeaking hinges.
Migratory Red-shouldered Hawks are also making feeding stops at area wetlands.
The Palm Warbler (Setophaga palmarum) is easily identified by its tail pumping behavior.  Look for it in shrubs along the river shoreline or near lakes and streams.  Palm Warblers are among the earliest of the warblers to move through in the spring.

The springtime show on the water continues…

Common Loons will continue migrating through the area during the upcoming month.
Buffleheads are still transiting the watershed.
Horned Grebes are occurring on the river and on local lakes.
Seeing these one-year-old male Hooded Mergansers, the bachelors, wandering around without any adult males or females is a good sign.  The adults should have moved on to the breeding grounds and local pairs should be well into a nesting cycle by now.  Hatching could occur any day.
Like Hooded Mergansers, Wood Ducks are cavity nesters, but their egg laying, incubation, and hatching often occurs a month or more later than that of the hoodies.  Judging by the attentiveness of the drake, this pair of woodies is probably in the egg-laying stage of its breeding cycle right now.
Redheads (Aythya americana) are stopping for a rest on their way north.
In spring, Double-crested Cormorants proceed up the river in goose-like flocks with adult birds like these leading the way.

Hey, what are those showy flowers?

That’s Lesser Celandine (Ficaria verna).  It’s often called Fig Buttercup.  In early April it blankets stream banks throughout the lower Susquehanna region.  If you don’t remember seeing it growing like that when you were younger, there’s a reason.  Lesser Celandine is an escape from cultivation that has become invasive.  While the appearance is tolerable; it’s the palatability that ruins everything.  It’s poisonous if eaten by people or livestock.
The Eastern Spring Beauty (Claytonia virginica) is a dainty native wildflower of riparian forests and other woodlands throughout the lower Susquehanna valley.
The Trout Lily (Erythronium americanum) is beginning to bloom now.  It’s a native of the region’s damp forests.
Virginia Bluebells (Mertensia virginica) is not native to the Susquehanna watershed, but neither is it considered invasive.  It creates colorful patches in riparian forests.
Dutchman’s Breeches (Dicentra cucullaria) is a strikingly beautiful native wildflower that grows on undisturbed forested slopes throughout the Susquehanna valley.

Wasn’t that refreshing?  Now go take a walk.

Clean Slate for 2020

Inside the doorway that leads to your editor’s 3,500 square foot garden hangs a small chalkboard upon which he records the common names of the species of birds that are seen there—or from there—during the year.  If he remembers to, he records the date when the species was first seen during that particular year.  On New Year’s Day, the results from the freshly ended year are transcribed onto a sheet of notebook paper.  On the reverse, the names of butterflies, mammals, and other animals that visited the garden are copied from a second chalkboard that hangs nearby.  The piece of paper is then inserted into a folder to join those from previous New Year’s Days.  The folder then gets placed back into the editor’s desk drawer beneath a circular saw blade and an old scratched up set of sunglasses—so that he knows exactly where to find it if he wishes to.

A quick glance at this year’s list calls to mind a few recollections.

The 2019 bird list included 48 species, the 47 on the board plus Ruby-throated Hummingbird, which was logged on a slip of paper found tucked into the edge of the frame.

This Green Frog, photographed on New Year’s Day 2019, was “out and about” along the edge of the editor’s garden pond.  Due to the recent mild weather, Green Frogs were active during the current New Year’s holiday as well.
On a day with strong south winds in late February or during the first two weeks of March, there is often a conspicuous northbound spring flight of migrating waterfowl, gulls, and songbirds that crosses the lower Susquehanna valley as it departs Chesapeake Bay.  These Tundra Swans were among the three thousand seen from the garden patio on March 13, 2019.  A thousand migrating Canada Geese, 500 Red-winged Blackbirds, numerous Ring-billed Gulls, and some Herring Gulls were seen during the same afternoon.
This juvenile Cooper’s Hawk was photographed through the editor’s kitchen window.  From its favorite perch on this arbor it would occasionally find success snagging a House Sparrow from the large local flock.  It first visited the garden in November, the species being absent there since early spring.  Unlike previous years, there was no evidence of a breeding pair in the vicinity during 2019.
Plantings that provide food and cover for wildlife are essential to their survival.  Native flowers including Trumpet Vine (Campsis radicans) and Partridge Pea provide nourishment for the Ruby-throated Hummingbirds that visit the editor’s garden, but they really love a basket or pot filled with Mexican Cigar (Cuphea ignea) too.  The latter (seen here) can be grown as a houseplant and moved outdoors to a semi-shaded location in summer and early fall.  But remember, it’s tropical, so you’ll need to bring it back inside when frost threatens.
A Swamp Sparrow is an unusual visitor to a small property surrounded by paved parking lots and treeless lawns.  Nevertheless, aquatic gardens and native plants helped to attract this nocturnal migrant, seen here eating seeds from Indiangrass.  It arrived on September 30 and was gone on October 2.

Before putting the folder back into the drawer for another year, the editor decided to count up the species totals on each of the sheets and load them into the chart maker in the computer.

Despite the habitat improvements in the garden, the trend is apparent.  Bird diversity has not cracked the 50 species mark in 6 years.  Despite native host plants and nectar species in abundance, butterfly diversity has not exceeded 10 species in 6 years.

It appears that, at the very least, the garden habitat has been disconnected from the home ranges of many species by fragmentation.  His little oasis is now isolated in a landscape that becomes increasingly hostile to native wildlife with each passing year.  The paving of more parking areas, the elimination of trees, shrubs, and herbaceous growth from the large number of rental properties in the area, the alteration of the biology of the nearby stream by hand-fed domestic ducks, light pollution, and the outdoor use of pesticides have all contributed to the separation of the editor’s tiny sanctuary from the travel lanes and core habitats of many of the species that formerly visited, fed, or bred there.  In 2019, migrants, particularly “fly-overs”, were nearly the only sightings aside from several woodpeckers, invasive House Sparrows (Passer domesticus), and hardy Mourning Doves.  Even rascally European Starlings became sporadic in occurrence—imagine that!   It was the most lackluster year in memory.

The Tufted Titmouse was a daily visitor to the garden through 2018.  This one was photographed investigating holes in an old magnolia there during the spring of that year.  There were no Tufted Titmouse sightings in the garden in 2019.  This and other resident species, especially cavity-nesters, appear to be experiencing at least a temporary decline.
Breeding birds including Northern Cardinals may have had a difficult year.  In the editor’s garden, a pair were still feeding and escorting one of their young in early October.  The infestation of the editor’s town by domestic house and feral cats may have contributed to the failure of earlier broods, but a lack of food is also a likely factor.

If habitat fragmentation were the sole cause for the downward trend in numbers and species, it would be disappointing, but comprehendible.  There would be no cause for greater alarm.  It would be a matter of cause and effect.  But the problem is more widespread.

Although the editor spent a great deal of time in the garden this year, he was also out and about, traveling hundreds of miles per week through lands on both the east and the west shores of the lower Susquehanna.  And on each journey, the number of birds seen could be counted on fingers and toes.  A decade earlier, there were thousands of birds in these same locations, particularly during the late summer.

At about the time of summer solstice in June each year, Common Grackles begin congregating into roving summer flocks that will grow in size to assure their survival during the autumn migration, winter season, and return north in the spring.  From his garden, the editor saw just one flock of less than a dozen birds during the summer of 2019.  He saw none during his journeys through other areas of the Susquehanna valley.  Flocks of one hundred birds or more did not materialize until the southbound movements of grackles passed through the region in October and November.

In the lower Susquehanna valley, something has drastically reduced the population of birds during breeding season, post-breeding dispersal, and the staging period preceding autumn migration.  In much of the region, their late-spring through summer absence was, in 2019, conspicuous.  What happened to the tens of thousands of swallows that used to gather on wires along rural roads in August and September before moving south?  The groups of dozens of Eastern Kingbirds (Tyrannus tyrannus) that did their fly-catching from perches in willows alongside meadows and shorelines—where are they?

Several studies published during the autumn of 2019 have documented and/or predicted losses in bird populations in the eastern half of the United States and elsewhere.  These studies looked at data samples collected during recent decades to either arrive at conclusions or project future trends.  They cite climate change, the feline infestation, and habitat loss/degradation among the factors contributing to alterations in range, migration, and overall numbers.

There’s not much need for analysis to determine if bird numbers have plummeted in certain Lower Susquehanna Watershed habitats during the aforementioned seasons—the birds are gone.  None of these studies documented or forecast such an abrupt decline.  Is there a mysterious cause for the loss of the valley’s birds?  Did they die off?  Is there a disease or chemical killing them or inhibiting their reproduction?  Is it global warming?  Is it Three Mile Island?  Is it plastic straws, wind turbines, or vehicle traffic?

The answer might not be so cryptic.  It might be right before our eyes.  And we’ll explore it during 2020.

A clean slate for 2020.

In the meantime, Uncle Ty and I going to the Pennsylvania Farm Show in Harrisburg.  You should go too.  They have lots of food there.

Some Autumn Insects

With autumn coming to a close, let’s have a look at some of the fascinating insects (and a spider) that put on a show during some mild afternoons in the late months of 2019.

Bush Katydids (Scudderia species) are found in brushy habitats and along rural roadsides.  Their green summer color fades to brown, maroon, and gold to match the autumn foliage where they hide.  Bush katydids often remain active until a hard freeze finally does them in.
The Eastern Buck Moth (Hemileuca maia) is fuzzy, appearing to wear a warm coat for its autumn expeditions.  Adults emerge in October and may fly as late as December.  Females deposit their eggs on the twigs of Bear Oak (Quercus ilicifolia), Blackjack Oak (Q. marilandica), or Chestnut Oak (Q. montana), trees that, in our region, seem most favorable for the moth’s use when growing on burned barrens and mountain slopes.  The spiny caterpillars are known to feed only on the foliage of these few trees.  In the lower Susquehanna valley, the Eastern Buck Moth is rare because its specialized habitat is in short supply, and it’s all Smokey The Bear’s fault.
The Sachem (Atalopedes campestris) wanders north from the Atlantic Coastal Plain into the Susquehanna valley each summer.  In some years they become the most numerous small orange butterfly of all, particularly around home gardens.  The larvae will feed on Crabgrass (Digitaria species), but have not found success overwintering this far north.  By November, adults begin to look pretty drab.
From 1978 through 1982, the Asian Multicolored Lady Beetle (Harmonia axyridis) was introduced into the eastern states by the United States Department of Agriculture.  It has become a nuisance in many areas where it swarms, sometimes bites, and often overwinters in large smelly masses within homes and other warm buildings.  As you may have guessed, it’s possibly displacing some of the less aggressive native lady beetle species.
On a chilly afternoon, a sun-warmed Bold Jumping Spider (Phidippus audax) pounced and dispatched this sluggish worker Honey Bee (Apis mellifera) that was trying to gather pollen from a late-season Purple Coneflower bloom.  This spider is bold indeed.
Under bridges, inside bird nest boxes, and sometimes beneath porches, the female Pipe Organ Mud Dauber (Trypoxylon politum), a predatory wasp, builds these elaborate nests composed of long rows (pipes) of nursery cells.  Into each cell one or more paralyzed spiders is deposited along with one of the female’s eggs.  When hatched, each larva will feed upon the paralyzed spider(s) inside its cell, then pupate.  The pupae overwinter, then emerge from their cells as adults during the following spring.  In the autumn, males often stand guard at an entrance to the nest to prevent parasitic species, including some flies (look at the fifth pipe from the right), from laying eggs on the pupae.  These wasps are not aggressive toward humans.
A Black-and-yellow Mud Dauber (Sceliphron caementarium) observes a neighboring nest of Common Paper Wasps (Polistes exclamans).  The Common Paper Wasp, a species also known as the Guinea Paper Wasp, is a native of the southern United States.  It is currently expanding its range into the lower Susquehanna valley from the Atlantic Coastal Plain.  These two wasp species and the Pipe Organ Mud Dauber are known to regularly coexist.  All three will take advantage of man-made structures for their nest sites.  People using the picnic tables beneath this pavilion roof never noticed the hundreds of docile wasps above.
Those moody Eastern Yellowjackets (Vespula maculifrons) can get very temperamental during warm autumn days.  These wasps may appear to have no enemies, but away from areas impacted by man’s everyday activities, they do.  The Robber Fly (Promachus species) hunts like a flycatcher or other woodland bird, waiting on a perch along the forest’s edge for prey to pass by, then ambushing it, yellowjackets included.
The invasive Spotted Lanternfly, a native of eastern Asia, continues to spread destruction.  It established itself throughout much of the east side of the lower Susquehanna River during the summer and fall of 2019.  Their route of travel across the farmlands of the region intersects with plenty of vineyards to obliterate and few, if any, natural enemies.  Expect them to begin colonizing the west shore en masse during 2020.
In 2020, plan to roll a few Spotted Lanternflies over, enjoy the view, and wait for the crimson tide to pass.  With any luck, they’ll peak in a year or two.

SOURCES

Eaton, Eric R., and Kenn Kaufman.  2007.  Kaufman Field Guide to Insects of North America.  Houghton Mifflin Company.  New York, NY.

Noxious Benefactor

It’s sprayed with herbicides.  It’s mowed and mangled.  It’s ground to shreds with noisy weed-trimmers.  It’s scorned and maligned.  It’s been targeted for elimination by some governments because it’s undesirable and “noxious”.  And it has that four letter word in its name which dooms the fate of any plant that possesses it.   It’s the Common Milkweed, and it’s the center of activity in my garden at this time of year.  Yep, I said milk-WEED.

Now, you need to understand that my garden is small—less than 2,500 square feet.  There is no lawn, and there will be no lawn.  I’ll have nothing to do with the lawn nonsense.  Those of you who know me, know that the lawn, or anything that looks like lawn, and I are through.

Anyway, most of the plants in the garden are native species.  There are trees, numerous shrubs, some water features with aquatic plants, and filling the sunny margins is a mix of native grassland plants including Common Milkweed.  The unusually wet growing season in 2018 has been very kind to these plants.  They are still very green and lush.  And the animals that rely on them are having a banner year.  Have a look…

The flowers of the Common Milkweed were exceptionally fragrant this year.  At their peak in early June, their hyacinth-or lilac-like aroma was so prevalent, it drifted into the house and overwhelmed the stink of the neighbor’s filthy dumpster that he had placed 12 feet away from my walls (100 feet from his).
Common Milkweed attracts a pollinating Greenbottle Fly (Lucilia species).  The dumpster attracts the invasive House Fly (Musca domestica), carrier of dysentery, typhoid, and other wonderful diseases.  Are you following this?  Remember as we proceed, milkweed is noxious.
Busy Eastern Carpenter Bees (Xylocopa virginica) load up with pollen from the flowers of the Common Milkweed.
A Red Milkweed Beetle (Tetraopes tetrophthalmus) munches on a tender fresh Common Milkweed leaf in mid-June.
Following the pollination of the flowers, seed pods will begin to grow.  I trim these off the plants.  The removal of the extra weight allows most of the stems to remain erect through stormy weather.  You’ll still get new plants from underground runners.  As you may have guessed, I’m trying to keep these plants upright and strong to host Monarch butterfly larvae.

I’ve planted a variety of native grassland species to help support the milkweed structurally and to provide a more complete habitat for Monarch butterflies and other native insects.  This year, these plants are exceptionally colorful for late-August due to the abundance of rain.  The warm season grasses shown below are the four primary species found in the American tall-grass prairies and elsewhere.

Big Bluestem, a native warm-season grass in flower.
Little Bluestem (Schizachyrium scoparium “Fort Indiantown Gap”) in flower.  This variety grows on the tank range at the military base where the armored vehicles and prescribed burns substitute for the  herd animals and fires of the prairie to prevent succession and allow it to thrive.
Partridge Pea can tolerate sandy soil and is a host plant for vagrant Cloudless Sulphur butterflies.
Black-eyed Susan (Rudbeckia hirta) is a popular native grassland wildflower.
Indiangrass (Sorghastrum nutans) in flower.  This and the other native plants shown here are available as seed from Ernst Seed Company in Meadville (PA).  They have an unbelievably large selection of indigenous species.  You can plant a small plot or acres and acres using really good mixes blended for purposes ranging from reclaiming pipeline right-of-ways and strip mines to naturalizing backyard gardens.
A Red Admiral (Vanessa atalanta) butterfly, a migratory species like the Monarch, on Purple Coneflower (Echinacea purpurea).  Yes, it is that Echinacea.

There was Monarch activity in the garden today like I’ve never seen before—and it revolved around milkweed and the companion plants.

A female Monarch laying eggs on a Common Milkweed leaf.
A third instar Monarch caterpillar with Oleander Aphids (Aphis nerii) on a Common Milkweed leaf.  Both of these insect species absorb toxins from the milkweed which makes them distasteful to predators.
Fifth instar (left and center) and fourth instar (right) monarch caterpillars devour a Common Milkweed leaf.  There were over thirty of these caterpillars in just a ten by ten feet area this morning.  I hope if you’re keeping a habitat for Monarchs, you’re enjoying the same fortune right now!
A slow-moving Monarch stopped for a break after making the circuit to deposit eggs on milkweed throughout the garden.
Third instar (top), fourth instar (right), and fifth instar (left) Monarch caterpillars quickly consume the leaf of a Common Milkweed plant.  Caterpillars emerging from eggs deposited today may not have sufficient late-season food to complete the larval segment of their life cycle.  Need more milkweed!
After benefitting from the nourishment of the Common Milkweed plant, a fifth instar Monarch caterpillar begins pupation on Big Bluestem grass.
Two hours later, the chrysalis is complete.
Another chrysalis, this one on flowering Switchgrass just two feet away from the previous one.  An adult Monarch will emerge from this pupa to become part of what we hope will be the most populated southbound exodus for the species in over five years.
There it is, soon ready to fly away.  And all courtesy of the noxious milkweed.
A chrysalis can often be found on man-made objects too.  This one is on the rim of a flower pot.
Ornamental flowers can attract adult Monarch butterflies seeking nectar.  I am now more careful to select seeds and plants that have not been treated with neonicotinoid insecticides.  There’s growing concern over the impact these compounds may be having on pollinating species of animals.  Oh…and I don’t mow, whack, cut, mutilate, or spray herbicides on my milkweed  But you probably figured that out already.

 SOURCES

Eaton, Eric R., and Kenn Kaufman.  2007.  Kaufman Field Guide to Insects of North America.  Houghton Mifflin Company.  New York.

Living in the Shadows

They get a touch of it here, and a sparkle or two there.  Maybe, for a couple of hours each day, the glorious life-giving glow of the sun finds an opening in the canopy to warm and nourish their leaves, then the rays of light creep away across the forest floor, and it’s shade for the remainder of the day.

The flowering plants which thrive in the understory of the Riparian Woodlands often escape much notice.  They gather only a fraction of the daylight collected by species growing in full exposure to the sun.  Yet, by season’s end, many produce showy flowers or nourishing fruits of great import to wildlife.  While light may be sparingly rationed through the leaves of the tall trees overhead, moisture is nearly always assured in the damp soils of the riverside forest.  For these plants, growth is slow, but continuous.  And now, it’s show time.

So let’s take a late-summer stroll through the Riparian Woodlands of Conewago Falls, minus the face full of cobwebs, and have a look at some of the strikingly beautiful plants found living in the shadows.

Oxeye (Heliopsis helianthoides) is common on the interior and along the edges of Riparian Woodland.  Specimens in deep shade flower less profusely and average less than half the height of the five feet tall inhabitants of edge environs.
Pale Touch-Me-Not (Impatiens pallida) is one of two species of native Impatiens found in the river floodplain.  Both are known as Jewelweed.  The stems and leaves of the indigenous Impatiens retain a great quantity of water, so life in filtered sunlight is essential to prevent desiccation.  Contrary to popular folklore, extracts of Jewelweed plants are not effective treatments of Poison Ivy (Toxicodendron radicans) contact dermatitis.
Spotted Touch-Me-Not (Impatiens capensis) is typically found in wetter soil than I. pallida.  Both Jewelweeds develop popping capsules which help to distribute the seeds of these annual wildflowers.  “Touch Me Not”, or you’ll be wearing tiny seeds.
Green-headed Coneflower (Rudbeckia laciniata) grows to heights of eight feet in full sun, hence its alternate common name, Tall Coneflower.  In deep shade, it may not exceed two feet in height.  Floodplains are the prime domain of this perennial.
Wingstem (Verbesina alternifolia) normally flowers no earlier than late August.  The bases of the leaves are continued onto the stem of the plant to form wings which extend downward along its length.  This wildflower tolerates shade, but flowers more profusely along the woodland edge.
Great Lobelia (Lobelia siphilitica), or Great Blue Lobelia, is a magnificent wetland and moist woodland wildflower, usually attaining three feet in height and adorned with a plant-topping spike of blossoms.  Invasive Japanese Stiltgrass (Microstegium vimineum) can be seen here competing with this plant, resulting in a shorter, less productive Lobelia.  Stiltgrass was not found in the Susquehanna River floodplain at Conewago Falls until sometime after 1997.  It has spread to all areas of woodland shade, its tiny seeds being blown and translocated along roads, mowed lots, trails, and streams to quickly colonize and overtake new ground.
American Bladdernut (Staphylea trifolia), a shrub of shaded woods, develops inflated capsules which easily float away during high water to distribute the seeds contained inside.
Buttonbush (Cephalanthus occidentalis) is a shrub of wet soils which produces a strange spherical flower, followed by this globular seed cluster.
Common Pawpaw (Asimina triloba) is a colony-forming small tree which produces a fleshy fruit.  It is the host plant for the caterpillars of the Zebra Swallowtail.  The plant and the butterfly approach the northern limit of their geographic range at Conewago Falls.
Common Spicebush (Lindera benzoin) is a widespread understory shrub in wet floodplain soils.  It is the host plant for the caterpillars of the Spicebush Swallowtail (Papilio troilus).
Sweet Autumn Virgin’s Bower (Clematis terniflora) is an escape from cultivation which has recently naturalized in the edge areas of the Conewago Falls Riparian Woodlands.  This vine is very showy when flowering and producing seed, but can be detrimental to some of the understory shrubs upon which it tends to climb.

SOURCES

Long, David; Ballentine, Noel H.; and Marks, James G., Jr.  1997.  Treatment of Poison Ivy/Oak Allergic Contact Dermatitis With an Extract of Jewelweed.  American Journal of Contact Dermatitis.  8(3): pp. 150-153.

Newcomb, Lawrence.  1977.  Newcomb’s Wildflower Guide.  Little, Brown and Company.  Boston, Massachusetts.

Beauties

It’s tough being good-looking and liked by so many.  You’ve got to watch out, because popularity makes you a target.  Others get jealous and begin a crusade to have you neutralized and removed from the spotlight.  They’ll start digging to find your little weaknesses and flaws, then they’ll exploit them to destroy your reputation.  Next thing you know, people look at you as some kind of hideous scoundrel.

Today, bright afternoon sunshine and a profusion of blooming wildflowers coaxed butterflies into action.  It was one of those days when you don’t know where to look first.

A Pearl Crescent (Phyciodes tharos) sipping nectar from Rough Boneset (Eupatorium pilosum) flowers.  Asters (Aster) are the host plants for the larvae of this butterfly.
A Buckeye (Junonia coenia) on Rough Boneset.  Its caterpillars are known to feed on members of the Acanthus family, possibly including the Water Willow (Justicia americana) which is so abundant in Conewago Falls.
Visitors from south of the Mason-Dixon Line arrived on the recent warm winds.  Two Cloudless Sulphurs (Phoebis sennae) patrolled the Riverine Grasslands, especially near the stands of Partridge Pea, a possible host plant.  One is seen here visiting a Halbred-leaved Rose Mallow blossom.  These large yellow butterflies are always a standout.

Purple Loosestrife (Lythrum salicaria) has a bad reputation.  Not native to the Americas, this prolific seed producer began spreading aggressively into many wetlands following its introduction.  It crowds out native plant species and can have a detrimental impact on other aquatic life.  Stands of loosestrife in slow-moving waters can alter flows, trap sediment, and adversely modify the morphology of waterways.  Expensive removal and biological control are often needed to protect critical habitat.

The dastardly Purple Loosestrife may have only two positive attributes.  First, it’s a beautiful plant.  And second, it’s popular; butterflies and other pollinators find it to be irresistible and go wild over the nectar.

A Silver-spotted Skipper (Epargyreus clarus) feeding on Purple Loosestrife nectar.  The host plants for this common butterfly’s caterpillars are a wide variety of Legumes.
A Cabbage White (Pieris rapae), a butterfly introduced from Europe in the 1800s, feeds on introduced Purple Loosestrife.
A Wild Indigo Duskywing (Erynnis baptisiae) feeding on Purple Loosestrife. This butterfly has expanded its population and range by using the introduced Crown Vetch as a host plant.

Don’t you just adore the wonderful butterflies.  Everybody does.  Just don’t tell anyone that they’re pollinating those dirty filthy no-good Purple Loosestrife plants.

SOURCES

Brock, Jim P., and Kenn Kaufman.  2003.  Butterflies of North America.  Houghton Mifflin Company.  New York.

Newcomb, Lawrence.  1977.  Newcomb’s Wildflower Guide.  Little, Brown and Company.  Boston, Massachusetts.

Summer Grasses

It has not been a good summer if you happen to be a submerged plant species in the lower Susquehanna River.  Regularly occurring showers and thunderstorms have produced torrents of rain and higher than usual river stages.  The high water alone wouldn’t prevent you from growing, colonizing a wider area, and floating several small flowers on the surface, however, the turbidity, the suspended sediment, would.  The muddy current casts a dirty shadow on the benthic zone preventing bottom-rooted plants from getting much headway.  There will be smaller floating mats of the uppermost leaves of these species.  Fish and invertebrates which rely upon this habitat for food and shelter will find sparse accommodation…better luck next year.

Due to the dirty water, fish-eating birds are having a challenging season as they try to catch sufficient quantities of prey to feed themselves and their offspring.  A family of Ospreys (Pandion haliaetus) at Conewago Falls, including recently fledged young, were observed throughout this morning and had no successful catches.  Of the hundred or more individual piscivores of various species present, none were seen retrieving fish from the river.  The visibility in the water column needs to improve before fishing is a viable enterprise again.

Ospreys competing for a suitable fishing perch.  Improving water conditions in the coming week should increase their success as predators.
Versatile at finding food, adult Bald Eagles are experienced and know to be on the lookout for Ospreys with fish, a meal they can steal through intimidation.

While the submerged plant communities may be stunted by 2017’s extraordinary water levels, there is a very unique habitat in Conewago Falls which endures summer flooding and, in addition, requires the scouring effects of river ice to maintain its mosaic of unique plants.  It is known as a Riverine Grassland or scour grassland.

The predominant plants of the Riverine Grasslands are perennial warm-season grasses.  The deep root systems of these hardy species have evolved to survive events which prevent the grassland from reverting to woodland through succession.  Fire, intense grazing by wild herd animals, poor soils, drought, and other hardships, including flooding and ice scour, will eliminate intolerant plant species and prevent an area from reforesting.  In winter and early spring, scraping and grinding by flood-driven chunk ice mechanically removes large woody and poorly rooted herbaceous growth from susceptible portions of the falls.  These adverse conditions clear the way for populations of species more often associated with North America’s tall grass prairies to take root.  Let’s have a look at some of the common species found in the “Conewago Falls Pothole Rocks Prairie”.

Big Bluestem (Andropogon gerardi), seen here growing in the cracks of a pothole rock. High water nourishes the plant by filling the crevices with nutrient-loaded sediment. This species evolved with roots over three feet deep to survive fires, trampling by bison, and drought.
Freshwater Cordgrass (Spartina pectinata) does well with its roots in water.  It creates exceptional bird habitat and grows in the falls and on ice-scoured small islands in free-flowing segments of the Susquehanna River downstream.
Switchgrass (Panicum virgatum), like Big Bluestem, is one of the tall grass prairie species and, like Freshwater Cordgrass, grows in near pure stands on ice-scoured islands.  It takes flooding well and its extensive root system prevents erosion.
Though not a grass, Water Willow (Justicia americana) is familiar as a flood-enduring emergent plant of river islands, gravel bars, and shorelines where its creeping rhizome root system spreads the plant into large masses.  These stands are often known locally as “grass beds”.  This member of the acanthus family provides habitat for fish and invertebrates among its flooded leaves and stems.  Its presence is critical to aquatic life in a year such as this.

The Conewago Falls Riverine Grassland is home to numerous other very interesting plants.  We’ll look at more of them next time.

SOURCES

Brown, Lauren.  1979.  Grasses, An Identification Guide.  Houghton Mifflin Company.  New York, NY.

Fussy Eaters

She ate only toaster pastries…that’s it…nothing else.  Every now and then, on special occasions, when a big dinner was served, she’d have a small helping of mashed potatoes, no gravy, just plain, thank you.  She received all her nutrition from several meals a week of macaroni and cheese assembled from processed ingredients found in a cardboard box.  It contains eight essential vitamins and minerals, don’t you know?  You remember her, don’t you?

Adult female butterflies must lay their eggs where the hatched larvae will promptly find the precise food needed to fuel their growth.  These caterpillars are fussy eaters, with some able to feed upon only one particular species or genus of plant to grow through the five stages, the instars, of larval life.  The energy for their fifth molt into a pupa, known as a chrysalis, and metamorphosis into an adult butterfly requires mass consumption of the required plant matter.  Their life cycle causes most butterflies to be very habitat specific.  These splendid insects may visit the urban or suburban garden as adults to feed on nectar plants, however, successful reproduction relies upon environs which include suitable, thriving, pesticide-free host plants for the caterpillars.  Their survival depends upon more than the vegetation surrounding the typical lawn will provide.

The Monarch (Danaus plexippus), a butterfly familiar in North America for its conspicuous autumn migrations to forests in Mexico, uses the milkweeds (Asclepias) almost exclusively as a host plant.  Here at  Conewago Falls, wetlands with Swamp Milkweed (Asclepias incarnata) and unsprayed clearings with Common Milkweed (A. syriaca) are essential to the successful reproduction of the species.  Human disturbance, including liberal use of herbicides, and invasive plant species can diminish the biomass of the Monarch’s favored nourishment, thus reducing significantly the abundance of the migratory late-season generation.

Monarch caterpillar after a fourth molt.  The fifth instar feeding on Swamp Milkweed.
A fifth molt begets the Monarch pupa, the chrysalis, from which the showy adult butterfly will emerge.
Adult Monarch feeding on Goldenrod (Solidago) nectar.

Butterflies are good indicators of the ecological health of a given environment.  A diversity of butterfly species in a given area requires a wide array of mostly indigenous plants to provide food for reproduction.  Let’s have a look at some of the species seen around Conewago Falls this week…

An adult Silvery Checkerspot (Chlosyne nycteis) visiting a nectar plant, Partridge Pea (Chamaecrista fasciculata).  Wingstem (Verbesina alternifolia), a plant of the Riparian Woodlands, is among the probable hosts for the caterpillars.
A Gray Hairstreak (Strymon melinus) visits Crown Vetch, a possible host plant.  Other potential larval food in the area includes Partridge Pea, Halberd-leaved Rose Mallow (Hibiscus laevis) of the river shoreline, and Swamp Rose Mallow (Hibiscus moscheutos), a plant of wetlands.
The Eastern Tailed Blue (Cupido comyntas) may use Partridge Pea , a native wildflower species, and the introduced Crown Vetch (Securigera/Coronilla varia) as host and nectar plants at Conewago Falls.
The Least Skipper (Ancyloxypha numitor) is at home among tall grasses in woodland openings, at riverside, and in the scoured grassland habitat of the Pothole Rocks in the falls.  Host plants available include Switchgrass (Panicum vigatum), Freshwater Cordgrass (Spartina pectinata), and Foxtails (Setaria).
The Zabulon Skipper (Poanes zabulon) is an inhabitant of moist clearings where the caterpillars may feed upon Lovegrasses (Eragrostis) and Purpletop (Tridens flavus).
The Eastern Tiger Swallowtail (Papilio glaucus), a female seen here gathering nectar from Joe-Pye Weed (Eutrochium), relies upon several forest trees as hosts. Black Cherry (Prunus serotina), Willow (Salix), Yellow Poplar (Liriodendron tulipifera), also known as Tuliptree, and Green Ash (Fraxinus pennsylvanica) are among the local species known to be used.  The future of the latter food species at Conewago Falls is doubtful.  Fortunately for the Eastern Tiger Swallowtail, the “generalist” feeding requirements of this butterfly’s larvae enable the species to survive the loss of a host plant.
A female Eastern Tiger Swallowtail, black morph, gathering nectar from Joe-Pye Weed.
The Zebra Swallowtail (Protographium marcellus), an adult seen here on Joe-Pye Weed, feeds exclusively upon Pawpaw (Asimina) trees as a caterpillar.  This butterfly species may wander, but its breeding range is limited to the moist Riparian Woodlands where colonial groves of Pawpaw may be found.  The Common Pawpaw (Asimina triloba), our native species in Pennsylvania, and the Zebra Swallowtail occur at the northern edge of their geographic ranges in the Lower Susquehanna River Watershed.  Planting Pawpaw trees as an element of streamside reforestation projects certainly benefits this marvelous butterfly.

The spectacularly colorful butterflies are a real treat on a hot summer day.  Their affinity for showy plants doubles the pleasure.

By the way, I’m certain by now you’ve recalled that fussy eater…and how beautiful she grew up to be.

SOURCES

Brock, Jim P., and Kaufman, Kenn.  2003.  Butterflies of North America.  Houghton Mifflin Company.  New York, NY.