
Photo of the Day


LIFE IN THE LOWER SUSQUEHANNA RIVER WATERSHED
A Natural History of Conewago Falls—The Waters of Three Mile Island

If you’ve visited Middle Creek Wildlife Management Area anytime during the past month, you may have noticed quite a bit of activity around the large pole-mounted nest boxes placed out in the open fields.








LEARN HOW LAND MANAGERS UTILIZE PRESCRIBED FIRE
This coming Saturday, April 18, 2026, beginning at 10 A.M. (rain date April 25), the Pennsylvania Game Commission is hosting a “Prescribed Fire Festival” at Middle Creek Wildlife Management Area. Be certain to come out to the visitor’s center at 100 Museum Road, Stevens, PA, for this event. Land managers will be there to answer questions and to explain the planning and preparations involved in overseeing a prescribed burn. There will be guided walks of habitats preserved using fire of varying intensities. You’ll see the equipment and protective clothing used by certified personnel to administer a live prescribed fire burn right before your eyes. Then you can have lunch—food trucks will be available on site.

After the burn demonstration, why not go for a walk or drive around the refuge. You can take note of how grassland and early successional plant communities are responding to previous doses of prescribed fire…


And how the grassland animals respond as well…








The fate of an avian predator such as a kestrel lies at the mercy of the fate of its quarry. Because, you see, the sun’s energy, after being converted to chemical energy by photosynthesizing plants, flows upward through the trophic levels of the food chain—herbivores (primary consumers) such as rodents and insects to carnivores (secondary and tertiary consumers) including kestrels. Grasslands, when abundant and diverse, are correspondingly abundant and diverse with small mammals and insects and will therefore support thriving populations of American Kestrels and other predators. These secondary and sometimes tertiary consumers fulfill a role in cultivating healthier populations of their prey, the primary and secondary consumers in the food web, as a balanced component of a flourishing grassland ecosystem. Sparse and fragmented grasslands, on the other hand, beget negligible small mammal and insect populations, are stricken with broken food webs, and champion few if any American Kestrels or other predators. If the land it occupies is neat, tidy, manicured, exploited, or sprayed sterile and dead, the energy flow cycle of the ecosystem is dead as well. There’s nothing animal introductions, reintroductions, rescues, culling, stocking, or harvesting can do about it, because in the end, it’s all about the habitat.
Here are some sights and sounds from the ongoing emergence of Brood XIV Periodical Cicadas in the Lower Susquehanna River Watershed.
We begin in the easternmost spur of the lower basin where a sizeable emergence of cicadas can be seen and heard in the woodlands surrounding the headwaters of the Conestoga River in Berks County north of Morgantown. This flight extends east into Chester County and the French Creek drainage of the Schuylkill River watershed on State Game Lands 43 north of Elverson and consists of Pharaoh Periodical Cicadas (Magicicada septendecim), the most common species among 17-year broods.












From Route 82 north of Elverson to the west through the forested areas along Route 10 north of Morgantown and the Pennsylvania Turnpike, we found an abundance of Cassin’s Periodical Cicadas (Magicicada cassini) calling among the Pharaohs. This mix of Pharaoh and Cassin’s Periodical Cicadas extends west along the north side of the turnpike into Lancaster County and State Game Lands 52 on Black Creek north of Churchtown.






Further west in Cornwall, Lebanon County, a Brood XIV emergence can be found on similar forested terrain: the Triassic hills of the Newark Basin—rich in iron ore and renowned for furnace operations during the eighteenth and nineteenth centuries. Pharaoh Periodical Cicadas were the only species heard among this population that extends from Route 72 east through the woodlands along Route 322 into the northern edge of State Game Lands 156 in Lancaster County.
On the west side of the Susquehanna, yet another isolated population of Brood XIV Periodical Cicadas can be found in Perry County, just south of Duncannon on State Game Lands 170 on the slopes of “Cove Mountain”, the canoe-shaped convergence of the western termini of Peters and Second Mountains.
Pharaoh Periodical Cicadas dominated this Perry County chorus,…
…but we did detect at least one Cassin’s Cicada trying to find a mate.

Not to say they aren’t present, but we have yet to detect the rarest species, Magicicada septendecula, the “Little Seventeen-year Cicada”, among the various populations of Brood XIV Periodical Cicadas emerging in the lower Susquehanna valley. For the coming two weeks or so until this brood is gone for another 17 years, the search continues.
For more on both annual and periodical cicada species in the Lower Susquehanna River Watershed, be sure to click the “Cicadas” tab at the top of this page!
Renowned for its smooth, light-gray bark and its large size, the American Beech is one the most easily recognized trees found in climax forests throughout the lower Susquehanna valley. Preferring rich soils, this shade tolerant native produces an abundance of nutritious nuts for wildlife including deer, turkey, grouse, squirrels, woodpeckers, and a variety of songbirds.
If you’ve visited a stand of beech trees lately, you may have noticed that the canopy seems a little sparse in comparison to the foliage of the oaks, poplars, and other hardwood species in the vicinity.

A closer look reveals the cause. And yes, it’s big, big trouble.




While treatment for BLD is possible, it must be done early. Protecting an entire stand in a forest can be prohibitively expensive, but if you have a specimen tree or small grove you think you might like to save, click here for a Penn State Extension guide with more information.
After repeatedly hearing the songs of these Neotropical migrants from among the foliage, we were finally able to get a look at them—but it required persistent effort.














Sometimes we have to count ourselves lucky if we see just one in five, ten, or even twenty of the birds we hear in the cover of the forest canopy or thicket. But that’s what makes this time of year so rewarding for the dedicated observer. The more time you spend out there, the more you’ll eventually discover. See you afield!


Despite what seemed to be a chilly early spring, the bright green leaves that unfold to close the canopy of our deciduous forests were dense and casting shade by the last days of April. For northbound migrants, this fresh foliage provides the cover they need for foraging, resting, and, for those that will stick around to breed in the lower Susquehanna valley, nesting.
We recall many occasions when sparse foliage during the first days of May seemed to delay the big push of Neotropical species, but the seasonal arrival of these birds in 2025 is thus far mostly ahead of schedule. This absence of delay is due in part to the lushness of the oaks. Some stands have not only leafed out, but are finished flowering and have added up to 12 inches of new branch growth. We spent these early hours of May among the oaks. Here’s a look at the Neotropical migrants and other species we found…








The movements of our migratory birds typically continue through much of the month of May. And peak numbers of Neotropical species often occur sometime during the second week of the month. But with habitat at the ready, favorable flight conditions could facilitate quick arrival and/or passage of the bulk of the remaining migrants during the coming week. You may want to venture out sooner rather than later—but watch your step!



Our wildlife has been having a tough winter. The local species not only contend with cold and stormy weather, but they also need to find food and shelter in a landscape that we’ve rendered sterile of these essentials throughout much of the lower Susquehanna valley’s farmlands, suburbs, and cities.
Planting trees, shrubs, flowers, and grasses that benefit our animals can go a long way, often turning a ho-hum parcel of property into a privately owned oasis. Providing places for wildlife to feed, rest, and raise their young can help assure the survival of many of our indigenous species. With a little dedication, you can be liberated from the chore of manicuring a lawn and instead spend your time enjoying the birds, mammals, insects, and other creatures that will visit your custom-made habitat.

Fortunately for us, our local county conservation districts are again conducting springtime tree sales offering a variety of native and beneficial cultivated plants at discount prices. Listed here are links to information on how to pre-order your plants for pickup in April. Click away to check out the species each county is offering in 2025!
Cumberland County Conservation District Annual Tree Seedling Sale—
Orders due by: Friday, March 21, 2025
Pickup on: Thursday, April 24, 2025 or Friday, April 25, 2025

Dauphin County Conservation District Seedling Sale—
Orders due by: Monday, March 17, 2025
Pickup on: Thursday, April 24, 2025 or Friday, April 25, 2025

Franklin County Conservation District Tree Seedling Sale—
Orders due by: Wednesday, March 19, 2025
Pickup on: Thursday, April 24, 2025

Lancaster County Annual Tree Seedling Sale—
Orders due by: Friday, March 7, 2025
Pickup on: Friday, April 11, 2025

Lebanon County Conservation District Tree and Plant Sale—
Orders due by: Monday, March 3, 2025
Pickup on: Friday, April 18, 2025




York County Conservation District Seedling Sale—
Orders due by: March 15, 2025
Pickup on: Thursday, April 10, 2025


If you live in Adams County, Pennsylvania, you may be eligible to receive free trees and shrubs for your property from the Adams County Planting Partnership (Adams County Conservation District and the Watershed Alliance of Adams County). These trees are provided by the Chesapeake Bay Foundation’s Keystone 10-Million Trees Partnership which aims to close a seven-year project in 2025 by realizing the goal of planting 10 million trees to protect streams by stabilizing soils, taking up nutrients, reducing stormwater runoff, and providing shade. If you own property located outside of Adams County, but still within the Chesapeake Bay Watershed (which includes all of the Susquehanna, Juniata, and Potomac River drainages), you still may have an opportunity to get involved. Contact your local county conservation district office or watershed organization for information.


We hope you’re already shopping. Need help making your selections? Click on the “Trees, Shrubs, and Woody Vines” tab at the top of this page to check out Uncle Tyler Dyer’s leaf collection. He has most of the species labelled with their National Wetland Plant List Indicator Rating. You can consult these ratings to help find species suited to the soil moisture on your planting site(s). For example: if your site has sloped upland ground and/or the soils sometimes dry out in summer, select plants with a rating such as UPL or FACU. If your planting in soils that remain moist or wet, select plants with the OBL or FACW rating. Plants rated FAC are generally adaptable and can usually go either way, but may not thrive or survive under stressful conditions in extremely wet or dry soils.
NATIONAL WETLAND PLANT LIST INDICATOR RATING DEFINITIONS
Using these ratings, you might choose to plant Pin Oaks (FACW) and Swamp White Oaks (FACW) in your riparian buffer along a stream; Northern Red Oaks (FACU) and White Oaks (FACU) in the lawn or along the street, driveway, or parking area; and Chestnut Oaks (UPL) on your really dry hillside with shallow soil. Give it a try.
As the autumn bird migration draws to a close for 2024, we’re delighted to be finding five of our favorite visitors from the coniferous and mixed forests of Canada and the northernmost continental United States.






While right now is the best time to get out and look for these species from the northern forests, any or all of them could linger into the winter months, particularly where the food supply is sufficient and conifers and other evergreens provide cover from the blustery weather.
The rain and clouds have at last departed. With blue skies and sunshine to remind us just how wonderful a spring afternoon can be, we took a stroll at Memorial Lake State Park in Lebanon County, Pennsylvania, to look for some migratory birds.








What? You thought we were gonna drop in on Maryland’s largest city for a couple of ball games and some oysters, clams, and crab cakes—not likely.
In recent days, the peak northbound push of migratory birds that includes the majority of our colorful Neotropical species has been slowed to a trickle by the presence of rain, fog, and low overcast throughout the Mid-Atlantic States. Following sunset last evening, the nocturnal flight resumed—only to be grounded this morning during the pre-dawn hours by the west-to-east passage of a fast-moving line of strong thundershowers. The NOAA/National Weather Service images that follow show the thunderstorms as well as returns created by thousands of migrating birds as they pass through the Doppler Radar coverage areas that surround the lower Susquehanna valley.





Just after 4 A.M., flashes of lightning in rapid succession repeatedly illuminated the sky over susquehannawildlife.net headquarters. Despite the rumbles of thunder and the din of noises typical for our urban setting, the call notes of nocturnal migrants could be heard as these birds descended in search of a suitable place to make landfall and seek shelter from the storm. At least one Wood Thrush and a Swainson’s Thrush (Catharus ustulatus) were in the mix of species passing overhead. A short time later at daybreak, a Great Crested Flycatcher was heard calling from a stand of nearby trees and a White-crowned Sparrow was seen in the garden searching for food. None of these aforementioned birds is regular here at our little oasis, so it appears that a significant and abrupt fallout has occurred.

Looks like a good day to take the camera for a walk. Away we go!















There’s obviously more spring migration to come, so do make an effort to visit an array of habitats during the coming weeks to see and hear the wide variety of birds, including the spectacular Neotropical species, that visit the Lower Susquehanna River Watershed each May. You won’t regret it!

Homo sapiens owes much of its success as a species to an acquired knowledge of how to make, control, and utilize fire. Using fire to convert the energy stored in combustible materials into light and heat has enabled humankind to expand its range throughout the globe. Indeed, humans in their furless incomplete mammalian state may have never been able to expand their populations outside of tropical latitudes without mastery of fire. It is fire that has enabled man to exploit more of the earth’s resources than any other species. From cooking otherwise unpalatable foods to powering the modern industrial society, fire has set man apart from the rest of the natural world.
In our modern civilizations, we generally look at the unplanned outbreak of fire as a catastrophe requiring our immediate intercession. A building fire, for example, is extinguished as quickly as possible to save lives and property. And fires detected in fields, brush, and woodlands are promptly controlled to prevent their exponential growth. But has fire gone to our heads? Do we have an anthropocentric view of fire? Aren’t there naturally occurring fires that are essential to the health of some of the world’s ecosystems? And to our own safety? Indeed there are. And many species and the ecosystems they inhabit rely on the periodic occurrence of fire to maintain their health and vigor.

Man has been availed of the direct benefits of fire for possibly 40,000 years or more. Here in the Lower Susquehanna River Watershed, the earliest humans arrived as early as 12,000 years ago—already possessing skills for using fire. Native plants and animals on the other hand, have been part of the ever-changing mix of ecosystems found here for a much longer period of time—millions to tens of millions of years. Many terrestrial native species are adapted to the periodic occurrence of fire. Some, in fact, require it. Most upland ecosystems need an occasional dose of fire, usually ignited by lightning (though volcanism and incoming cosmic projectiles are rare possibilities), to regenerate vegetation, release nutrients, and maintain certain non-climax habitat types.
But much of our region has been deprived of natural-type fires since the time of the clearcutting of the virgin forests during the eighteenth and nineteenth centuries. This absence of a natural fire cycle has contributed to degradation and/or elimination of many forest and non-forest habitats. Without fire, a dangerous stockpile of combustible debris has been collecting, season after season, in some areas for a hundred years or more. Lacking periodic fires or sufficient moisture to sustain prompt decomposition of dead material, wildlands can accumulate enough leaf litter, thatch, dry brush, tinder, and fallen wood to fuel monumentally large forest fires—fires similar to those recently engulfing some areas of the American west. So elimination of natural fire isn’t just a problem for native plants and animals, its a potential problem for humans as well.

To address the habitat ailments caused by a lack of natural fires, federal, state, and local conservation agencies are adopting the practice of “prescribed fire” as a treatment to restore ecosystem health. A prescribed fire is a controlled burn specifically planned to correct one or more vegetative management problems on a given parcel of land. In the Lower Susquehanna River Watershed, prescribed fire is used to…
Let’s look at some examples of prescribed fire being implemented right here in our own neighborhood…

























In Pennsylvania, state law provides landowners and crews conducting prescribed fire burns with reduced legal liability when the latter meet certain educational, planning, and operational requirements. This law may help encourage more widespread application of prescribed fire in the state’s forests and other ecosystems where essential periodic fire has been absent for so very long. Currently in the Lower Susquehanna River Watershed, prescribed fire is most frequently being employed by state agencies on state lands—in particular, the Department of Conservation and Natural Resources on State Forests and the Pennsylvania Game Commission on State Game Lands. Prescribed fire is also part of the vegetation management plan at Fort Indiantown Gap Military Reservation and on the land holdings of the Hershey Trust. Visitors to the nearby Gettysburg National Military Park will also notice prescribed fire being used to maintain the grassland restorations there.
For crews administering prescribed fire burns, late March and early April are a busy time. The relative humidity is often at its lowest level of the year, so the probability of ignition of previous years’ growth is generally at its best. We visited with a crew administering a prescribed fire at Middle Creek Wildlife Management Area last week. Have a look…

















Prescribed burns aren’t a cure-all for what ails a troubled forest or other ecosystem, but they can be an effective remedy for deficiencies caused by a lack of periodic episodes of naturally occurring fire. They are an important option for modern foresters, wildlife managers, and other conservationists.
It’s that time of year. Your local county conservation district is taking orders for their annual tree sale and it’s a deal that can’t be beat. Order now for pickup in April.
The prices are a bargain and the selection includes the varieties you need to improve wildlife habitat and water quality on your property. For species descriptions and more details, visit each tree sale web page (click the sale name highlighted in blue). And don’t forget to order packs of evergreens for planting in mixed clumps and groves to provide winter shelter and summertime nesting sites for our local native birds. They’re only $12.00 for a bundle of 10.

Cumberland County Conservation District Annual Tree Seedling Sale—
Orders due by: Friday, March 22, 2024
Pickup on: Thursday, April 18, 2024 or Friday, April 19, 2024



Dauphin County Conservation District Seedling Sale—
Orders due by: Monday, March 18, 2024
Pickup on: Thursday, April 18, 2024 or Friday, April 19, 2024

Lancaster County Annual Tree Seedling Sale—
Orders due by: Friday, March 8, 2024
Pickup on: Friday, April 12, 2024






Lebanon County Conservation District Tree and Plant Sale—
Orders due by: Friday, March 8, 2024
Pickup on: Friday, April 19, 2024




Perry County Conservation District Tree Sale—
Orders due by: Sunday, March 24, 2024
Pickup on: Thursday, April 11, 2024

Again this year, Perry County is offering bluebird nest boxes for sale. The price?—just $12.00.

York County Conservation District Seedling Sale—
Orders due by: Friday, March 15, 2024
Pickup on: Thursday, April 11, 2024

To get your deciduous trees like gums, maples, oaks, birches, and poplars off to a safe start, conservation district tree sales in Cumberland, Dauphin, Lancaster, and Perry Counties are offering protective tree shelters. Consider purchasing these plastic tubes and supporting stakes for each of your hardwoods, especially if you have hungry deer in your neighborhood.

There you have it. Be sure to check out each tree sale’s web page to find the selections you like, then get your order placed. The deadlines will be here before you know it and you wouldn’t want to miss values like these!
Recently, we found these Chestnut Oak acorns setting roots into the leaf litter to secure their place among the plants that will turn the forest understory green in the spring. Individual acorns that germinate soon after falling to the ground in autumn may avoid becoming food for squirrels, turkeys, deer, and other wildlife, thus increasing their chances of surviving to later become adult trees able to produce acorns that pass this quick-development trait to yet another generation of oaks.
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.

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 autumn leaves will be falling fast, so make it a point this weekend to check out the show on South Mountain.
If you’re feeling the need to see summertime butterflies and their numbers just don’t seem to be what they used to be in your garden, then plan an afternoon visit to the Boyd Big Tree Preserve along Fishing Creek Valley Road (PA 443) just east of U.S. 22/322 and the Susquehanna River north of Harrisburg. The Pennsylvania Department of Conservation and Natural Resources manages the park’s 1,025 acres mostly as forested land with more than ten miles of trails. While located predominately on the north slope of Blue Mountain, a portion of the preserve straddles the crest of the ridge to include the upper reaches of the southern exposure.

Fortunately, one need not take a strenuous hike up Blue Mountain to observe butterflies. Open space along the park’s quarter-mile-long entrance road is maintained as a rolling meadow of wildflowers and cool-season grasses that provide nectar for adult butterflies and host plants for their larvae.















Do yourself a favor and take a trip to the Boyd Big Tree Preserve Conservation Area. Who knows? It might actually inspire you to convert that lawn or other mowed space into much-needed butterfly/pollinator habitat.
While you’re out, you can identify your sightings using our photographic guide—Butterflies of the Lower Susquehanna River Watershed—by clicking the “Butterflies” tab at the top this page. And while you’re at it, you can brush up on your hawk identification skills ahead of the upcoming migration by clicking the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab. Therein you’ll find a listing and descriptions of hawk watch locations in and around the lower Susquehanna region. Plan to visit one or more this autumn!
This linear grove of mature trees, many of them nearly one hundred years old, is a planting of native White Oaks (Quercus alba) and Swamp White Oaks (Quercus bicolor).
Imagine the benefit of trees like this along that section of stream you’re mowing or grazing right now. The Swamp White Oak in particular thrives in wet soils and is available now for just a couple of bucks per tree from several of the lower Susquehanna’s County Conservation District Tree Sales. These and other trees and shrubs planted along creeks and rivers to create a riparian buffer help reduce sediment and nutrient pollution. In addition, these vegetated borders protect against soil erosion, they provide shade to otherwise sun-scorched waters, and they provide essential wildlife habitat. What’s not to love?

The following native species make great companions for Swamp White Oaks in a lowland setting and are available at bargain prices from one or more of the County Conservation District Tree Sales now underway…











So don’t mow, do something positive and plant a buffer!
Act now to order your plants because deadlines are approaching fast. For links to the County Conservation District Tree Sales in the Lower Susquehanna River Watershed, see our February 18th post.
County Conservation District Tree Sales are underway throughout the Lower Susquehanna River Watershed. Now is the time to order for pickup in April. The prices are a bargain and the selection is fabulous. For species descriptions and more details, visit each tree sale web page (click the sale name highlighted in blue). And don’t forget to order bundles of evergreens for planting in mixed clumps and groves to provide winter shelter and summertime nesting sites for our local birds. They’re only $12.00 for a bundle of 10—can’t beat that deal!
Cumberland County Conservation District Annual Tree Seedling Sale—
Orders due by: Friday, March 24, 2023
Pickup on: Thursday, April 20, 2023 or Friday, April 21, 2023


Dauphin County Conservation District Seedling Sale—
Orders due by: Monday, March 20, 2023
Pickup on: Thursday, April 20, 2023 or Friday, April 21, 2023

Lancaster County Annual Tree Seedling Sale—
Orders due by: Friday, March 10, 2023
Pickup on: Thursday, April 13, 2023

Lebanon County Conservation District Tree and Plant Sale—
Orders due by: Wednesday, March 8, 2023
Pickup on: Friday, April 7, 2023

Perry County Conservation District Tree Sale—(click on 2023 Tree Sale Brochure tab when it scrolls across the page)
Orders due by: March 22, 2023
Pickup on: Thursday, April 13, 2023








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.










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