Flying Phenomena

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!


While summer continues until September 22nd, the hints of the coming cold weather are all around us. The current sign nature is giving us is the raptor migration. At some unknown point in August, certain species of raptors find it appropriate to begin their long journey to warmer winter grounds. This segment of the Nine Minute Naturalist will discuss the raptor migration phenomena signaling the coming fall season.

Raptor migration in the eastern United States begins in late July through January but peaks from early September to November. Decreasing day length triggers “zuganrhue” or migratory restlessness. Seasonal timing varies by species. Early migrants are broad-winged hawks, osprey, bald eagles and kestrels. Mid-fall migrants are sharp-shinned and Cooper’s hawks. Our late season raptor migrants feature red-tailed and red-shouldered hawks. The timing of their southern journey is also caused by weather such as a strong cold front passing through.

The Blue Ridge Mountains are a key travel route for raptors leading to their wintering grounds. The key feature mountains offer is updraft. Raptors have perfected the art of soaring. Eagles, buteos (red-tailed, red-shouldered, broad-winged hawks) and vultures use soaring to travel 250-300 miles per day. These species prefer to use the updraft and thermal currents created by our mountains to fly in the most efficient manner possible. While they are efficient, these soaring species will travel a longer route. Birds such as osprey, falcons and harriers use more of a flapping technique. While more inefficient, they can utilize a much more direct routes across land or water.

While raptors are usually solitary creatures, migration causes flocking for some species. The most obvious example of this is the broad-winged hawk. This species forms flocks of migrants called kettles. When air currents are at their best, thousands of broad-winged hawks pass by the Rockfish Gap Hawk Watch location. Over the past decade, the peak migration day corresponds with the apex of the broad-winged hawk movements south. Three different days over the past decade saw over 10,000 broad-winged hawks migrate past. The highest total occurred September 17, 2019 when 10,643 broad-winged hawks flew past the bird counters. Over that time period, the highest number of birds were seen from September 17-26th. It is a marvel to see what appears as a coordinated movement of birds wheeling and circling into the sky upon the rising thermal winds.

The best way to view the raptor migration is from a vantage that covers both sides of the Blue Ridge. We are lucky enough to have multiple options in our immediate area. Humpback Rocks and Spy Rock offer viewsheds that meet that parameter. Time your arrival to these locations so that you get to watch for birds through the late morning and early afternoon. Thermals are caused when the sun differentially heats the earths surface. When the thermals begin you will see birds begin their wheeling ascent before they get to the right elevation to soar south. The official count is kept at the Rockfish Gap and is tallied daily from August 15th to the end of November. Visit this website to get a detailed account of the happenings at Rockfish Gap. This site has not only current sightings but decades of old data to peruse at your leisure.

The times are changing and for evidence look to the sky. Any overlook at Wintergreen or in our surrounding area will suffice to witness this event. Make sure you bring your binoculars and some patience to take in this yearly phenomenon.

 

Redtail

 

Kettle

From the Director

 

While The Nature Foundation’s doors remain closed to the public, many of our programs are alive and well. Some are virtual and others are live as we learn to live with the new normal and social distancing.

 

  • Guided hikes and outdoor programs are happening with limited numbers and masked participants. Our hiking guides are available in The Mountain Inn as well as the Blackrock Market. The Shoppe is executing some online sales and by appointment visits.

 

  • Our greenhouse has never been busier. We have over 1,500 mature native shrubs and a good assortment of wildflowers. The facility is usually open on Thursdays and Fridays from 9:30am till 4:30 pm. It’s always best to visit the website to select what you want and let us know from the contact information listed.

 

 

  • In October, we will host our first ever virtual Wildflower Symposium with a focus on all aspects of Natural History. Those who participate will also be supporting The Nature Foundation’s efforts at bringing the virtual learning experience to teachers and students in Nelson County’s Schools. Our instructors will design field trip videos and lectures that can be used to provide new information that students will not find in most current textbooks.

 

Our programs continue to evolve in the “new normal” as we continue to provide the science that enables the protection of Wintergreen and surrounding ecosystems, share our knowledge, and communicate by phone, zoom and email. We look forward to when we can see everyone in Trillium House but until then, enjoy the “nature of Wintergreen” with us. Immerse yourself in our hiking trails as you celebrate the beauty of an early fall season.

 

Doug Coleman
Biologist/Executive Director
The Nature Foundation at Wintergreen

Much Ado About Nothing

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!


The sight of an extensive web formed at the end of tree branch resulting in leaf defoliation is a cause of quite the commotion. This commotion is absolutely justifiable at certain times of the year. In the case of fall webworm, the commotion is much ado about nothing. This installment of the Nine Minute Naturalist will give an in depth look at this unsightly pest.

The fall webworm is native to Virginia and most of the United States. It will feed on over 100 tree species but is seen most often at Wintergreen on hickories, oaks and ash. This species tends to become a focal point of the forest landscape in late July through August. The eggs laid May to July hatch and the caterpillar immediately begins constructing a web around the terminal end of a branch, making it especially conspicuous. The caterpillar is identified by it’s white to pale yellow color with two lines of black dots down the back. As the caterpillar grows, the webs enlarge encircling more of the branch. The leaves are stripped except the midrib and larger veins in the leaf.

After reading this description of unsightly defoliation happening all over our forested landscape, I am sure you are wondering why is this much ado about nothing? The primary reason this is not considered a devastating forest pest is the timing. By mid to late summer, the process of photosynthesis has mostly shut down. As the day lengths begin to get shorter and shorter, the feeding of the leaves for the production of chlorophyll begins to abate and the large amount of nutrients goes to the seeds, such as acorns, and buds that will be next year’s leaves. When a pest comes along in August and begins to eat leaves on a tree, it adds very little stress to the tree since the process of leaf drop has already begun. The second major reason to not fret over your trees being loaded with webs at the moment is that since this is a native species there are built in control mechanisms. Native pests tend to have native predators that have adapted to take advantage of the increase in the prey volume. There are a host of wasps and birds that like to feed on fall webworm. There are reportedly 50 species of parasitoids and 36 predators that call fall webworm their prey. That is a lot of control on a year to year basis.

The best option to control this pest yourself, if you don’t feel like waiting for nature to regulate the problem for you, is to cut the branch off below the web and burn the it. Chemical application is not very effective on web caterpillars since it doesn’t penetrate the web to get on the leaves they are eating.

The 2020 summer has been a unique one to say the least and that includes our vast amount of fall webworm amongst the landscape. While the population is booming, I am confident the built-in control mechanisms will do their job and your trees will come through this scourge unaffected. The fall webworm, while unsightly, is much ado about nothing.

 

Fall webworm

 

Web

ACP Aftermath

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!


The idiom “nature abhors a vacuum”, although meant primarily for the world of physics, applies very nicely to the biological world and even more specifically to the Wintergreen ecosystem. Dominion Energy’s initial steps of preparing for the construction of the Atlantic Coast Pipeline (ACP) was to fell a portion of the forest along the pipeline path. The scars on the mountainside, while tragic, are in the process of healing. This week’s Nine Minute Naturalist will discuss the resilience of our forest and how nature is dealing with the ACP aftermath.

The hand felling along the path of the now cancelled (hopefully for good) Atlantic Coast Pipeline created a patch of early successional forest infrequently seen in our mature closed forest environment. The cutting in many ways imitated a natural disaster such as a tornado, derecho or some other blowdown. This man-made disaster was similar in that the trees were put on the ground, not removed and the soil was not disturbed. The lack of soil disturbance is important to the speed and quality of the regeneration. The cut area is currently in the scrub-shrub stage of development. This stage features vegetation dominated by shrubs and trees 1-10 years of age.

Nature is always prepared for the “vacuum” created by natural disasters or in this case, man-made natural disasters. The regeneration of a forest comes by different means. The seed bank is a very important aspect. Different seeds have different triggers to promote germination. Light and moisture are key to most species while some need scarification and others will require a cold overwintering period. Yellow poplar seeds can live in the seed bank for up to 8 years while other species such as ash and black cherry will live up to 3 years in the forest floor. The second way to quickly regenerate a forest is via sprouting. After being cut, many trees will either sprout new stems out of the root collars around the stump or out of their root system. Oaks and maples both put forth vigorous stump sprouts. American beech is best known for their ability to colonize an area via root sprouting.

A recent excursion to the site of the cutting illustrated the ability of the forest to recover quickly. The tree growth in the center of the cutting, where the most sun hits the forest floor, averages 10-20’ in height. On the edges the height ranges from 5-10’. The tree composition is a majority of desirables such as tulip poplar, black locust, black cherry and a variety of oak species. A majority of the trees are growing from seed which tends to yield higher quality specimens than stump sprouts. Some of these seedlings may have grown slowly in the understory and taken advantage of increased sun spurt in growth. A key benefit to the site not having been cleaned up by mechanized equipment is that the preexisting seedlings had a better chance of surviving and getting to the canopy quickly. Another benefit to minimal soil disturbance is the rebounding of the dense mountain laurel stand on the slope heading towards Fortunes Ridge. This dense mountain laurel stand covered the understory prior to being cut for sake of the pipeline. The good news is that the existing root systems are sprouting heavily and show great promise to dominate the understory once again in the near future.

The negative aspect to any forest disturbance is the opening for invasive species to take hold of space in the forest canopy. Throughout the cutting, royal paulownia and tree of heaven are occupying small bits of space. Despite their existence, the native early successional species such as tulip poplar and black locust are holding their own in terms of growth rates.

The ACP aftermath seems to be good news on all fronts. The best news is that the threat of further man-made damage seems to be abated. The forest growth and regeneration appear better than I could have hoped for and will quickly erase the ills done to it such a short time ago.

 

Tree growth

 

Oak seedling

 

Mountain laurel

The Nature Foundation’s summer intern, Carter Stanton, has been awarded the Virginia Native Plant Society grant to study the fringetree.

 

Fringetree is gorgeous when it blooms, and a lovely small tree the rest of the year. However, it is generally considered difficult to propagate; cuttings don’t root easily and seeds take multiple seasons to germinate. Developing more reliable propagation techniques will make it more widely available in native plant landscaping. In addition, it is related to ash, and we don’t know yet how it will be impacted by Emerald Ash Borer. The ability to propagate hardy and resistant trees is potentially very important right now for fringetree. A graduate student of mine, Carter Stanton, will be working at The Nature Foundation at Wintergreen’s propagation greenhouse this summer to test a variety of techniques, and Carter will also be monitoring fringetree in the wild for Emerald Ash Borer damage.

Janet Steven, Associate Professor Department of Organismal & Environmental Biology, Christopher Newport University

 

 

From the Director: Update 7/1/20

 

After consultation with The Nature Foundation at Wintergreen (TNFW) Staff, and medical associates, TNFW has made the decision to not reopen the Trillium House facility the weekend of July 10th as originally planned. Our organization is carefully monitoring the current COVID-19 health crisis, and we will continue to review our abilities to protect our staff, our members, and guests. It is our opinion that to open the Trillium House to the public at this time would be premature.  

We have started our outdoor guided hikes and workshops, however we are limiting the number of participants to allow for social distancing. We are taking the appropriate precautions, including social distancing and face coverings, when required in all programs and activities. Hike participants are being asked to meet our hike leaders at the Trillium House parking lot and drive their own vehicles to the trailheads. We request the hike participants to bring masks with them. Our trail maps can be purchased at the Mountain Inn front desk and at the Blackrock gas station. The map is also available on our website.  

Staff will continue to monitor messages via telephone and email. Our native plant list can be found on our website. Order plants and schedule appointment for pickup at our greenhouse via email to director@tnfw.org.

Also, please check out our website for “The Nine Minute Naturalist” and Peace Out(side) for virtual offerings. Our Facebook and Instagram pages are updated weekly with interesting information and activities.

Doug Coleman
Biologist/Executive Director
The Nature Foundation at Wintergreen

Monarch Migration

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!


One of the year’s most fascinating natural phenomena is the monarch migration. The fact that the entire population of one of our continent’s most beloved creatures overwinters in about 15 acres in Mexico and requires one specific plant to complete its lifecycle highlights the fragility of the monarch’s existence. This Nine Minute Naturalist will focus on what a complex life the monarch leads.

The first migration for monarchs begins and ends at two winter sanctuaries, The Cerro Pelon and Piedra Herrada. The monarchs leave their overwinter homes in late February and head north until early April. The females will lay eggs as they work their way north and then die ending migration one.

Migration two begins after generation two monarchs reach adulthood around late April/early May and will soon set off on their way northward. They will cease their northward journey by early June when they reach regions containing milkwood plants. Females lay eggs thus starting a new generation that will move in the opposite direction of the previous two generations.

Migration three begins the change in direction. Directional migration halts from early June to late July during which travel and reproduction are done on a local level. Movement during this time tends to go south/southwest but is much less defined than any other migration.

By the first week in August, the northern most monarchs (50 degrees north around Winnipeg) begin their legendary southward journey that will continue until early December. Migration four is a defined and well-known migration and is the longest in duration and length. This migration differs in that the monarchs do not mate and reproduce on their long southward journey.

Each generation tends to take 25-50 days from egg through pupation. Temperature is the greatest variable that dictates development time as well as reproduction success. Foul weather in the spring and fall tends to play a huge factor in population growth or crash. A survey done this past winter at the overwinter site in Mexico revealed a 53% decrease in the monarch population. The cause of the sudden decrease is attributed to poor weather during the spring and fall migrations. Loss of breeding habitat due to overuse of herbicide in industrial farming greatly decreases the amount of milkweed available to monarchs and thus aids to lower the population. The current populace is believed to be below the extinction threshold and has been nominated for protection under the Endangered Species Act.

I still get excited each time I see the monarchs migrating in both spring and fall. One easy way to facilitate monarch population growth is to manage your landscape for milkweed. Wintergreen’s landscape is full of milkweed varieties that need to be a focal point of each yard at Wintergreen. Over the next month, monarch volume will increase throughout the Blue Ridge migration route. Make sure you appreciate this yearly phenomena!

 

Monarch

 

Monarch caterpillar

 

Stinkin’ Spiders

by Josh Palumbo, Forest Management Coordinator

I welcome you to The Nature Foundation at Wintergreen’s attempt to bring some nature and knowledge into your home. The Nine Minute Naturalist borrows from NPR’s lovely 90-Second Naturalist podcast. Since we all have a bit more time on our hands, the goal is to take something that is happening out in our environment and stimulate your brain for roughly nine minutes. Don’t let something as “minor” as a quarantine to keep you from learning. I hope you enjoy!


Few topics may be less popular to discuss than spiders but alas the season of “spider web in the face” has arrived. From now until early fall, any venture into the woods will be rife with swinging arms and dramatic head movements as we attempt to elude new webs. If you are going to have spiders on your head, you should be knowledgeable of what you just made contact with. This session of the Nine Minute Naturalist will cover a few of the spiders that cause you to dream of cold, crisp days of autumn.

The first spider to appear in abundance at Wintergreen in the heat of mid to late summer is the spined micrathena spider. This mostly black spider is easily identified by the angular abdomen. They are a member of the spiny orb weavers group and are generally woodland spiders that love to build nests across the trails of Wintergreen. Our trails or any other opening in the forest floor act as fly ways for insects and thus tend to attract the interest of their predators. Their hard spiny body is most likely a defense against predation as it would make a less than ideal meal going down the throat of a larger predator. This spider is harmless to humans but does a great job decreasing the fly populations at Wintergreen.

Another common spider found primarily in August is the black and yellow garden spider, another member of the orb weaver family. This large spider, identified by its black and yellow coloring on the abdomen, is found more commonly in our landscape settings but is occasionally found in the woods. The black and yellow garden spider makes nests around knee to waist height with a distinct thick silk strand that zigzags down the middle of the nest. Although the large size of this spider is a bit intimidating, it is harmless to humans and does flee when disturbed.

The most visually intriguing spider that graces our presence in the late summer is the marbled orb spider. Also, a member of the orb weaver family, this spider is identified by an orange head and upper legs, black and white banded lower legs and a marbled abdomen. These large spiders are found primarily in the woodland realms of Wintergreen especially near our waterways. When their head high webs are disturbed, the marbled orb spider tends to get to cover on the ground and stay hidden until danger passes. This member of the orb weavers is most common in late August to early October. Though harmless to humans, these spiders act as great “organic” pest control.

Each of these spiders will be found quite often by anyone traveling along our trails and woodlands in the late summer months. I advise you walk with a proper spider web stick to clear your way as you cover ground but leave our natural pest control unharmed. Happy “spider web in the face season”!

 

Spined micrathena spider

 

Black and yellow garden spider

 

Marbled orb spider