Roses and Nettles (Rosales) – LIFE IN THE LOWER SUSQUEHANNA RIVER WATERSHED

January 26, 2024January 26, 2024

The Fog of a January Thaw

As week-old snow and ice slowly disappears from the Lower Susquehanna River Watershed landscape, we ventured out to see what might be lurking in the dense clouds of fog that for more than two days now have accompanied a mid-winter warm spell.

York Haven Dam Powerhouse — After freezing to a slushy consistency earlier this week, the Susquehanna is already beginning to thaw. Below the York Haven Dam at Conewago Falls, the water is open and ice-free.

Mallards and a pair of American Wigeon on a frozen lake. — On frozen man-made lakes and ponds, geese and ducks like these Mallards and American Wigeon are presently concentrated around small pockets of open water.

American Robin in a Callery pear — During the past ten days, American Robin numbers have exploded throughout the lower Susquehanna valley. The majority of these birds may be a mix of both those coming south to escape the late onset of wintry conditions to our north and those inching north into our region as early spring migrants.

American Robin — The January thaw has melted the snow from lawns and fields to provide thousands of visiting robins with a chance to forage for earthworms.

Cooper's Hawk — A visit by this young Cooper’s Hawk to the susquehannnawildlife.net headquarters garden sent songbirds scrambling…

…but did nothing to unnerve our resident Eastern Gray Squirrels,…

But earlier in the week, when heavy snow cover in the rural areas surrounding our urbanized neighborhood made it difficult for rodent-eating raptors to find food, we received brief visits from both a Red-tailed Hawk…

…and this young Red-shouldered Hawk, an uncommon bird of prey most often found in wet woods and other lowlands.

Red-shouldered Hawk in flight. — Unimpressed, each of our visiting buteos remained for just a few minutes before moving on in search of more favorable hunting grounds and prey.

Early Successional Growth — As snow melted and exposed bare ground in fields of early successional growth, we encountered…

…a flock of White-crowned Sparrows, most in first-winter plumage…

…and at least a dozen American Tree Sparrows. During the twentieth century, these handsome songbirds were regular winter visitors to the lower Susquehanna region. During recent decades, they’ve become increasingly more difficult to find. Currently, moderate numbers appear to be arriving to escape harsher weather to our north.

Adult Male Northern Harrier — What could be more appropriate on a foggy, gray evening than finding a “gray ghost” (adult male Northern Harrier) patrolling the fields in search of mice and voles.

If scenes of a January thaw begin to awaken your hopes and aspirations for all things spring, then you’ll appreciate this pair of closing photographs…

Pileated Woodpecker in Silver Maple — The maroon-red flower buds of Silver Maples are beginning to swell. And woodpeckers including Pileated Woodpeckers are beginning to drum, a timber-pounding behavior they use to establish breeding territories in habitats with suitable sites for cavity nesting.

In wet soil surrounding spring seeps and streams, Skunk Cabbage is rising through the leaf litter to herald the coming of a new season. Spring must surely be just around the corner.

January 3, 2024March 30, 2024

Birds of the Sunny Grasslands

With the earth at perihelion (its closest approach to the sun) and with our home star just 27 degrees above the horizon at midday, bright low-angle light offered the perfect opportunity for doing some wildlife photography today. We visited a couple of grasslands managed by the Pennsylvania Game Commission to see what we could find…

Grasslands and Hedgerows — On this State Game Lands parcel, prescribed fire is used to maintain a mix of grasslands and brushy early successional growth. In nearby areas, both controlled fire and mechanical cutting are used to remove invasive species from hedgerows and the understory of woodlots. Fire tolerant native species then have an opportunity to recolonize the forest and improve wildlife habitat. This management method also reduces the fuel load in areas with the potential for uncontrolled wildfires.

The sun-dried fruits of a Common Persimmon tree found growing in a hedgerow. — The sun-dried fruits of a native Common Persimmon tree found growing in a hedgerow.

Savanna-like Grasslands — Just one year ago, mechanical removal of invasive trees and shrubs (including Multiflora Rose) on this State Game Land was followed by a prescribed fire to create this savanna-like grassland.

Hundreds of Song Sparrows were found in the grasses and thickets at both locations.

White-throated Sparrows were also abundant, but prefer the tangles and shrubs of the thickets.

Northern Mockingbirds were vigilantly guarding winter supplies of berries in the woodlots and hedgerows.

In grasses and tangles on wetter ground, about a dozen Swamp Sparrows were discovered.

Dark-eyed Juncos were encountered only in the vicinity of trees and large shrubs.

Several Savannah Sparrows were observed. Though they’re mostly found in treeless country, this particular one happened to pose atop a clump of shrubs located within, you guessed it, the new savanna-like grasslands.

A tiny bird, even when compared to a sparrow, the Winter Wren often provides the observer with just a brief glimpse before darting away into the cover of a thicket.

Standing Clump of Timber — Within grasslands, scattered stands of live and dead timber can provide valuable habitat for many species of animals.

A "snag" with an excavated nest cavity. — Woodpeckers and other cavity-nesting birds rely upon an abundance of “snags” (standing dead trees) for breeding sites.

This Red-bellied Woodpecker and about a dozen others were found in trees left standing in the project areas.

A Yellow-bellied Sapsucker soaks up some sun.

This very cooperative Pileated Woodpecker seemed to be preoccupied by insect activity on the sun-drenched bark of the trees. This denizen of mature forests will oft times wander into open country where larger lumber is left intact.

Just as things were really getting fun, some late afternoon clouds arrived to dim the already fading daylight. Just then, this Northern Harrier made a couple of low passes in search of mice and voles hidden in the grasses.

October 27, 2023October 28, 2023

Visit South Mountain for the Brightest Foliage Display You’ve Ever Seen

Where should you go this weekend to see vibrantly colored foliage in our region? Where are there eye-popping displays of reds, oranges, yellows, and greens without so much brown and gray? The answer is Michaux State Forest on South Mountain in Adams, Cumberland, and Franklin Counties.

South Mountain is the northern extension of the Blue Ridge Section of the Ridge and Valley Province in Pennsylvania. Michaux State Forest includes much of the wooded land on South Mountain. Within or adjacent to its borders are located four state parks: King’s Gap Environmental Education Center, Pine Grove Furnace State Park, Caledonia State Park, and Mont Alto State Park. The vast network of trails on these state lands includes the Appalachian Trail, which remains in the mountainous Blue Ridge Section all the way to its southern terminus in Georgia.

Pennsylvania State Parks on South Mounatin — In Pennsylvania, the forested highlands of the Blue Ridge Section of the Ridge and Valley Province are known as South Mountain. Much of South Mountain lies within the boundaries of Michaux State Forest. Stars indicate the locations of 1) King’s Gap Environmental Education Center, 2) Pine Grove Furnace State Park, 3) Caledonia State Park, and 4) Mont Alto State Park. A drive on US 30 between Gettysburg and Chambersburg will take you right through Michaux State Forest along an east to west axis while a scenic northbound or southbound trip along PA 233 will bring you in proximity to each of the state parks located therein. (Base image from NASA Earth Observatory Collection)

If you want a closeup look at the many species of trees found in Michaux State Forest, and you want them to be labeled so you know what they are, a stop at the Pennsylvania State University’s Mont Alto arboretum is a must. Located next door to Mont Alto State Park along PA 233, the Arboretum at Penn State Mont Alto covers the entire campus. Planting began on Arbor Day in 1905 shortly after establishment of the Pennsylvania State Forest Academy at the site in 1903. Back then, the state’s “forests” were in the process of regeneration after nineteenth-century clear cutting. These harvests balded the landscape and left behind the combustible waste which fueled the frequent wildfires that plagued reforestation efforts for more than half a century. The academy educated future foresters on the skills needed to regrow and manage the state’s woodlands.

Online resources can help you plan your visit to the Arboretum at Penn State Mont Alto. More than 800 trees on the campus are numbered with small blue tags. The “List of arboretum trees by Tag Number” can be downloaded to tell you the species or variety of each. The interactive map provides the locations of individual trees plotted by tag number while the Grove Map displays the locations of groups of trees on the campus categorized by region of origin. A Founder’s Tree Map will help you find some of the oldest specimens in the collection and a Commemorative Tree Map will help you find dedicated trees. There is also a species list of the common and scientific tree names.

The Yellow Buckeye (Aesculus flava) is a tree found in the forests of the Blue Ridge Section of the Ridge and Valley Province in West Virginia, Virginia, North Carolina and Georgia. You can see it in Pennsylvania by visiting the collection of trees in the Arboretum at Penn State Mont Alto.

The American Chestnut can be difficult to find due to the impact of chestnut blight, but you can see it in the Arboretum at Penn State Mont Alto.

Shagbark Hickory is a common tree in the forests of South Mountain.

The Sweet Cherry (Prunus avium), a native of Europe, is naturalized throughout eastern and south-central Pennsylvania and is one of the more than 150 species of trees in the arboretum’s collection.

Sweet Birch (Betula lenta) foliage is particularly bright yellow on South Mountain this autumn. It really “pops” against the backdrop of the evergreen Eastern White Pines and Eastern Hemlocks. During less-than-ideal years, Sweet Birch leaves can subtly transition from green to drab brown without much fanfare before falling.

You might have a difficult time finding a Common Persimmon (Diospyros virginiana) growing wild in Pennsylvania, but you can find it in the Arboretum at Penn State Mont Alto.

The autumn leaves will be falling fast, so make it a point this weekend to check out the show on South Mountain.

June 18, 2023June 18, 2023

A Few Plants with Wildlife Impact in June

Here’s a look at some native plants you can grow in your garden to really help wildlife in late spring and early summer.

The Larger Blue Flag (Iris versicolor) and Soft Rush (Juncus effusus) in flower in mid-June. — The showy bloom of a Larger Blue Flag (Iris versicolor) and the drooping inflorescence of Soft Rush (Juncus effusus). These plants favor moist soils in wetlands and damp meadows where they form essential cover and feeding areas for insects, amphibians, and marsh birds. Each is an excellent choice for helping to absorb nutrients in a rain garden or stream-side planting. They do well in wet soil or shallow water along the edges of garden ponds too.

The fruits of Smooth Shadbush (Amelanchier laevis), also known as Allegheny Serviceberry, Smooth Serviceberry, or Smooth Juneberry, ripen in mid-June and are an irresistible treat for catbirds, robins, bluebirds, mockingbirds, and roving flocks of Cedar Waxwings.

Common Milkweed and Eastern Carpenter Bee — Also in mid-June, the fragrant blooms of Common Milkweed attract pollinators like Eastern Carpenter Bees,…

Common Milkweed and Honey Bee — …Honey Bees,…

Common Milkweed and Banded Hairstreak — …and butterflies including the Banded Hairstreak (Satyrium calanus). In coming weeks, Monarch butterflies will find these Common Milkweed plants and begin laying their eggs on the leaves. You can lend them a hand by planting milkweed species (Asclepias) in your garden. Then watch the show as the eggs hatch and the caterpillars begin devouring the foliage. Soon, they’ll pupate and, if you’re lucky, you’ll be able to watch an adult Monarch emerge from a chrysalis!

May 14, 2023May 14, 2023

Mother’s Day Flowers

Let’s have a look at some of the magnificent native wildflowers blooming on this Mother’s Day in forests and thickets throughout the Lower Susquehanna River Watershed.

Rue Anemone (Thalictrum thalictroides) is a fragile little wildflower of open woods.

The Blackhaw (Viburnum prunifolium) is a shrub of thickets and forest borders. The flower clusters mature into an abundance of berries relished by birds and other wildlife.

A large Black Cherry tree adorned in white blossoms can be pleasing to the eye and very beneficial for pollinating insects.

The Common Pawpaw is a small tree of damp well-drained soils. Where conditions are ideal, it may form clonal colonies in the forest understory. The deep maroon blooms mature into banana-like fruits, hence its alternate common name “Custard Apple”.

The Mayapple or Mandrake (Podophyllum peltatum) commonly blankets the forest floor. It, like other ephemeral wildflowers, is vulnerable to invasions by non-native shrubs that leaf out earlier in spring than native species and rob them of sunlight during their already abbreviated growing season.

Aren’t they spectacular?

Why not take a stroll to have a look at these and other plants you can find growing along a nearby woodland trail? You could check out some place new and get a little exercise too!

If you go, please tread lightly, take your camera, mind your manners, and…

October 29, 2022

Photo of the Day

The harmless, herbivorous Northern Walkingstick (Diapheromera femorata), also known as the Common Walkingstick, is well camouflaged when among the twigs and stems of deciduous trees. As foliage drops in autumn, these wingless insects often descend to ground level and sometimes venture into view. This individual was found in the vicinity of ideal habitat: a portion of forest including Black Cherry and Black Oak (Quercus velutina) trees. Juvenile Northern Walkingsticks feed on the leaves of the former, adults on those of the latter.

October 19, 2022October 20, 2022

Photo of the Day

Earlier today, these migrants were found feeding on berries along the edge of a forest clearing in northern Lebanon County, Pennsylvania. Can you find the three Hermit Thrushes among the early successional growth seen here? For extra credit, identify the three species of berry-producing pioneer plants that are shown. For additional credit, which one of these plants is a non-native invasive species? Click the image to see how you did.

August 17, 2022September 15, 2022

Photo of the Day

Gray Catbird and Black Chokeberry — The fruits of a Black Chokeberry (Aronia melanocarpa) prove irresistible to this Gray Catbird. Chokeberry is a native clump-forming shrub that reaches a height of less than ten feet. It is tolerant of wet soils and makes a good choice for inclusion in plantings alongside streams and ponds, as well as in rain gardens. Springtime clusters of white flowers yield berries by this time each summer. By turning red as the fruits ripen, the foliage helps attract not only catbirds, but robins, waxwings, and other species that, in exchange for a meal, will assure dispersal of the plant’s seeds in their droppings. With considerable sweetening, tart chokeberries can be used for juicing and the creation of jams, jellies, and preserves.

May 15, 2022May 15, 2022

Photo of the Day

Birds of Conewago Falls in the Lower Susquehanna River Watershed: Baltimore Oriole — A male Baltimore Oriole sings from the upper reaches of a Northern Hackberry to establish a nesting territory and attract a mate.

April 16, 2022April 16, 2022

Photo of the Day

Invasive Trees and Plants of the Lower Susquehanna River Watershed: Callery Pear including Bradford Pear — Presently in the valleys of the Lower Susquehanna River Watershed, you’re sure to see a gorgeous nightmare, showy stands of flowering Callery Pear (Pyrus calleryana). Invasive groves like this one quickly dominate successional habitat and often create monocultures, often excluding native pioneer trees like Eastern Red Cedar and several species of deciduous hardwood. The void beneath the pear trees in this photograph shows how deer browsing can intensify the damage, preventing other plant species from becoming established in the understory. In autumn, crimson foliage again makes these non-native trees a standout in the landscape. The red leaves attract birds including American Robins and Cedar Waxwings to the abundant berries, but European Starlings usually get to them first. Planted specimens of ornamental Callery Pears began producing fertile seeds when multiple varieties became available in addition to the self-sterile “Bradford Pears” that were planted widely during the last decades of the twentieth century. Cross-pollination between varieties produces the fertile seeds that are distributed by starlings and other birds as they digest the fruit.

March 23, 2021August 15, 2022

Forest vs. Woodlot

Let’s take a quiet stroll through the forest to have a look around. The spring awakening is underway and it’s a marvelous thing to behold. You may think it a bit odd, but during this walk we’re not going to spend all of our time gazing up into the trees. Instead, we’re going to investigate the happenings at ground level—life on the forest floor.

Rotting logs and leaf litter create the moisture retaining detritus in which mesic forest plants grow and thrive. Note the presence of mosses and a vernal pool in this damp section of forest.

The earliest green leaves in the forest are often those of the Skunk Cabbage (Simplocarpus foetidus). This member of the arum family gets a head start by growing in the warm waters of a spring seep or in a stream-fed wetland. Like many native wildflowers of the forest, Skunk Cabbage takes advantage of early-springtime sun to flower and grow prior to the time in late April when deciduous trees grow foliage and cast shade beneath their canopy.

Among the bark of dead and downed trees, the Mourning Cloak butterfly (Nymphalis antiopa) hibernates for the winter. It emerges to alight on sun-drenched surfaces in late winter and early spring.

Another hibernating forest butterfly that emerges on sunny early-spring days is the Eastern Comma (Polygonia comma), also known as the Hop Merchant.

In a small forest brook, a water strider (Gerridae) chases its shadow using the surface tension of the water to provide buoyancy. Forests are essential for the protection of headwaters areas where our streams get their start.

Often flooded only in the springtime, fish-free pools of water known as vernal ponds are essential breeding habitat for many forest-dwelling amphibians. Unfortunately, these ephemeral wetland sites often fall prey to collecting, dumping, filling, and vandalism by motorized and non-motorized off-roaders, sometimes resulting in the elimination of the populations of frogs, toads, and salamanders that use them.

Wood Frogs (Lithobates sylvaticus) emerge from hiding places among downed timber and leaf litter to journey to a nearby vernal pond where they begin calling still more Wood Frogs to the breeding site.

Wood Frog eggs must hatch and tadpoles must transform into terrestrial frogs before the pond dries up in the summertime. It’s a risky means of reproduction, but it effectively evades the enormous appetites of fish.

When the egg laying is complete, adult Wood Frogs return to the forest and are seldom seen during the rest of the year.

In early spring, Painted Turtles emerge from hideouts in larger forest pools, particularly those in wooded swamps, to bask in sunny locations.

Dead standing trees, often called snags, are essential habitats for many species of forest wildlife. There is an entire biological process, a micro-ecosystem, involved in the decay of a dead tree. It includes fungi, bacteria, and various invertebrate animals that reduce wood into the detritus that nourishes and hydrates new forest growth.

Birds like this Red-headed Woodpecker feed on insects found in large snags and nest almost exclusively in them. Many species of wildlife rely on dead trees, both standing and fallen, during all or part of their lives.

There certainly is more to a forest than the living trees. If you’re hiking through a grove of timber getting snared in a maze of prickly Multiflora Rose (Rosa multiflora) and seeing little else but maybe a wild ungulate or two, then you’re in a has-been forest. Logging, firewood collection, fragmentation, and other man-made disturbances inside and near forests take a collective toll on their composition, eventually turning them to mere woodlots. Go enjoy the forests of the lower Susquehanna valley while you still can. And remember to do it gently; we’re losing quality as well as quantity right now—so tread softly.

The White-tailed Deity in a woodlot infested by invasive tangles of Multiflora Rose.

October 31, 2020August 17, 2022

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!

August 7, 2017August 27, 2023

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…