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We’re in stick season – the transition period after the leaves have fallen and before the snow comes. Without the cover of deciduous leaves, it’s easier to see the last of the fall migrating birds passing through and the arrival of the first winter visitors. Here are some birds to watch for:

Snow geese migrate in flocks of tens of thousands from their northern breeding grounds in the Canadian High Arctic to winter along the mid-Atlantic coast. In New England, peaking from mid-October through November, flocks settle down in farmlands to rest and eat. They fly in big compact flocks and have a stunning cylindrical landing pattern known as “the toilet bowl flush.” While their migration path has shifted more to the New York side of Lake Champlain in recent years, there are still lots of birds to be seen at the wildlife viewing area on VT Route 17 in Addison in the Dead Creek Wildlife Management Area.

Northern New England’s and Canada’s red-tailed hawk migration peaks in November. Hawks in the more southern part of their range stay put, and red-taileds are becoming less migratory in the northern portion of their range. Alone or in small flocks, red-tailed hawks concentrate along shoreline peninsulas, to avoid crossing large open water. They migrate during the day to take advantage of thermals – columns of rising warm air – and soar over 79% of the time.

Among the last waterfowl migrants to head south, all North American populations of common mergansers migrate generally short to intermediate distances. Their migration peaks in mid-November. The birds we see in the winter on large lakes are likely not the same birds that breed here. They migrate over land at night and along seacoasts or major river systems by day. Common mergansers are also among the first waterfowl to return in the spring, moving north as soon as the ice begins breaking up on inland lakes and rivers.

Late October through mid-November is peak migration for juvenile common loons. While adults depart earlier in the autumn, young loons need time to strengthen their wing and chest muscles for flight, as it can take up to a quarter mile of vigorous flapping to lift off. Loons overwinter in the ocean from the Gulf of Maine down the Atlantic coast, and one-and-two year old common loons remain in their wintering grounds throughout the year.

We’re starting to see visitors from the north begin to arrive now as well. Be on the lookout for snow buntings, rough-legged hawks, snowy owls, and winter finches (finch forecast).

What caused the hole in this goldenrod ball gall?

A hungry downy woodpecker! The goldenrod ball gall was providing food and shelter to a cream-colored plump larva of a goldenrod gall fly. A neat conical hole is the sign that a downy woodpecker (hairy woodpeckers are too big to perch on the goldenrod stalks) retrieved a nutritious snack. Research suggests that downy woodpeckers tap on the galls to locate the fly’s emergence tunnel (which the gall fly excavated in the fall) so they will have less gall to excavate. 

Black-capped chickadees are also predators of goldenrod ball gall fly larvae. Since chickadees don’t have the powerful beak of the downy woodpecker, they grab and pull apart the gall instead, leaving larger and messier holes. Other holes you may observe on goldenrod ball galls are the emergence holes of the goldenrod gall flies (around 2mm wide) or their wasp or beetle parasites (around 1mm wide).

Likely a chickadee-excavated gall on left (in which a spider has taken up residence) and adult goldenrod ball gall fly exit hole on the right. 

“…Well, come on all you people,

gather ‘round.

Break down and listen to…

decomposition…”

–Decomposition by Steve Van Zandt and the Banana Slug String Band

With pumpkins all around at this time of year, there’s ample opportunity to watch decomposition in action. Leave your jack-o-lanterns out to observe the process. 

How does the color change?

How does the texture change?

How does the smell change?

How does the shape change?

What creatures do you notice visiting the pumpkin? 

Here are some books to go along with the pumpkin decomposition observations:

“The leaves are gone from the hillsides and the glory of the red maple and of the yellow aspen and birch is strewn upon the ground. Only in the protected swamps is there any color, the smoky gold of the tamaracks…these are days of quietly falling needles when after each breath of wind the air is smoky with their drift.”

– The Singing Wilderness by Sigurd Olson

We’re in the brief and brilliant days of the tamarack’s smoky gold. Tamarack, also known as larch, is the only northern conifer that sheds all of its leaves in the fall. Tamaracks are adapted to cold climates and waterlogged soils, and thus have taken a leaf strategy in between the deciduous and coniferous trees in our region. 

Like other deciduous trees, tamarack’s leaves are efficient, lightweight, and relatively cheap (they don’t need a waxy coating to protect them in winter and thus require less carbon and nutrients than evergreen needles). Tamaracks also can reabsorb a high proportion of nitrogen from their leaves before they are shed. 

Like other coniferous trees, tamarack’s leaves are needle-shaped. The small clusters of needles are sparsely positioned along the branch, ensuring most leaves are amply exposed to sunlight and able to photosynthesize. A needle shape also has less surface area compared to the broad leaves of other deciduous trees, making conifer leaves more wind resistant.

After the smoky gold has left the trees and drifted quietly to the ground, we’ll still have piles of (slightly drabber) smoky gold needles surrounding the tamaracks, a last remembrance of the brilliant fall colors before the snow arrives. 

Why are there green stripes on the otherwise yellow and brown quaking aspen leaves? 

If you look closely at the base of the green splotch, there is a brown pocket of leaf tissue and the upper petiole (leaf stem) is swollen. Who is inside? 

A tiny and very hungry caterpillar! This 2mm long caterpillar secretes a chemical that prevents the natural deterioration of a section of the leaf. With chlorophyll retained and photosynthesis continuing, the larva keeps its food source alive. The caterpillar will exit the leaf to spend the winter as a pupa and emerge next spring as a tiny moth. 

A brilliant and ephemeral season is upon us: fall foliage. As the temperatures drop and the days get shorter, a corky layer of cells – the abscission layer – begins to form at the end of deciduous leaf stems. This layer prevents the transport of materials between the leaf and the rest of the tree. Chlorophyll, the green pigment that absorbs the sun’s energy to transform carbon dioxide and water into carbohydrates, is no longer able to be replaced and slowly breaks down and disappears. 

Without that green chlorophyll, the yellow and orange pigments – xanthophylls and carotenoids – that were concealed in the warmer months are revealed. Some trees (such as birches, aspens, elms, beeches, hickories, american basswoods) merely unmask these shades of lemon and honey. 

Other trees produce red pigments – anthocyanins. These mix with yellows to create flaming crimsons and purples. A succession of warm, sunny days and cool, crisp but not freezing nights brings about the most spectacular color displays. During these days, lots of sugars are produced in the leaf but the cool nights and the gradual closing of veins going into the leaf prevent these sugars from moving out. Lots of sugar and light spur production of the brilliant anthocyanin pigments.

Why is there so much variation in color between trees and even leaves on the same tree? Each maple leaf produces its own combination of green, yellow, orange, and red depending on how much sugar is trapped in the leaf, how close to dying it is, and how much light it is getting. On any one maple, there should be leaves in all stages of coloration and if you watch one leaf from day to day, you will see it change.

How many shades of leaf color can you find?!

Yesterday marked the shift from summer to fall – the autumn equinox in the Northern Hemisphere. The sun rose due east on the horizon and set due west. Now the sun’s arc grows lower and further south with each sunrise and sunset, making shorter days and longer shadows, until we celebrate the winter solstice.

Looking for outdoor activity ideas this fall? Four Winds has created a guide with play prompts, materials to have on hand, recommended gear, and non-fiction and fiction books. What will you try?!

https://fwni.org/wp-content/uploads/2022/09/SeasonalActivityResources_FWNI_fall.pdf

“…This grasshopper, I mean —

the one who has flung herself out of the grass,

the one who is eating sugar out of my hand…”

–excerpt of The Summer Day by Mary Oliver

These late summer days are the time of grasshoppers. In places it seems as if they are blanketing the grass as dozens take wing with your every step. This is the final rush of grasshopper life – the brief adult period where grasshoppers mate and lay eggs before they die with the hard frosts. Grasshoppers go through simple metamorphosis. A grasshopper lays her eggs in the soil, and in the spring tiny nymphs hatch out, able to hop away from predators within minutes. They feed on grasses and other plants and grow quickly, molting four or five times over three months or so before they reach the adult stage with wings. Several generations hatch during the summer, so adults and nymphs of different sizes are often found at the same time. 

Look closely at grasshoppers at this time of year. How many different kinds of grasshoppers can you find? There are 36 species in Vermont, according to the Vermont Orthoptera Atlas. Grasshopper have short antennae compared to the long antenna of crickets and katydids.

Can you jump like a grasshopper nymph? Fly like a grasshopper adult? 

Find a male and a female grasshopper? 

Uncovering frass trumpets, collecting insects, tracing shadows, and searching for spider webs – this autumn in more than 50 schools across Vermont, New Hampshire, New York, and Massachusetts, hundreds of volunteers and thousands of students and classroom teachers are once again starting their school year with The Nature Program.

Below are some snapshots from Four Winds’ trainers as they prepare for their first workshops of the school year, focusing on one of The Nature Program’s five different yearlong concepts.

In the Ecosystems concept we meet some animals and plants that are part of different ecosystems and consider the interactions we observe as we explore the out-of-doors. Signs of Leaf Eaters introduces the idea of a food web and the energy flow from sun to plants to animals.

In our Patterns in Nature concept we practice sorting and classifying as well as describing and recording why objects or organisms belong in a certain group. We learn what makes an insect an insect in All Sorts of Insects, and through outdoor observations of common insects we learn to recognize patterns that help us classify them into groups.

When we study the Earth concept, explorations start with the sun as the engine that powers Earth’s major systems. In Sunlight and Shadow we see how and why we experience day and night and the seasons, and we’ll consider how sunlight supplies the energy for photosynthesis, fuels the water cycle, and provides the right conditions for life.

Throughout Structure and Function we compare different organisms as we think about how physical and behavioral characteristics relate to important functions in their lives and how they affect each organism’s ability to live and grow and have offspring. In Spiders – Web-builders and Wanderers, we take a close look at spiders, noting special structures like spinnerets, pedipalps, and fangs.

During the year of studying Cycles, we meet different plants and animals, learning about their life cycles in the turning of the seasons. In Insect Life Cycles we explore how insects go through distinct stages as they develop, undergoing metamorphosis as they change from young to adult.

With five different yearlong concepts to explore together, our Nature Program volunteers AND the children with whom they’re learning all have many opportunities to be outside really getting to know nearby nature. 

What are the white TicTac-like structures hanging off the back of this tobacco hornworm (larva of Carolina sphinx moth)?

These are the cocoons of a Braconid wasp (Cotesia congregata)! The female adult wasps use their long ovipositors to lay eggs inside a live hornworm caterpillar, along with viruses that take down the internal defense responses of the hornworm. The larvae hatch inside the caterpillar and feed on their host. After 12-16 days, the wasp larvae chew through the skin of the dying caterpillar to spin their silken cocoons. About 4-8 days later the 2-3mm adult wasps emerge and fly off, following chemical scents released by the damaged plants and feeding caterpillars to find more hornworms. 

To discourage tobacco hornworms in your tomatoes, allow the wasps to complete their metamorphosis – they will cause the host caterpillar to feed slowly and die before pupating and will also release more parasitoid wasps.