The equinox is past and autumn quietly proceeds at Bear Creek. The Queen Anne’s Lace closes into delicate, lacy balls and fewer Canada Goldenrod glow in the sun. Chipmunks and squirrels feast on a variety of nuts, storing some for the coming season. Small butterflies dance above a variety of purple and white asters that still flourish in the white sunlight of early fall. As autumn changes occur, though, nature produces new life and sets its sights on spring. Grasshoppers and katydids sing in the park now as they find their mates who will lay their eggs in the soil for the coming year. Tiny crickets emerge, foraging in the tall grass. Flowers continue ripening and sowing their seed for next spring and summer. And, surprise! Some eggs hatched this week in Bear Creek! Nature uses autumn to prepare for winter, but also to make plans for a glorious spring.
Seeds and Nuts Galore: A Feast for Birds and Animals
The late summer native flowers are still blooming steadily, not yet ready to set seed, but soaking in the pale light of shorter days. Here a huge bouquet of New England Asters (Symphyotrichum novae-angliae) shines in morning sunlight as the Canada Goldenrod (Solidago canadensis) just behind begins to fade.
In my twenty or so years at Bear Creek, I don’t remember the Smooth Asters (Symphyotrichum laeve)and Panicled Asters (Symphyotrichum lanceolatum) ever being as lush as they are this year. All the fields have large swathes of these lavender and white beauties mixed up together.
And a small aster has made its appearance as well, the Calico Aster (Symphyotrichum lateriflorum). I love how the centers range from yellow to rose.
The summer flowers are ripening their seeds, readying to spread them into the park for next year’s meadows. This week I watched a Black-Capped Chickadee (Poecile atricapillus) playfully make a meal of the seeding heads of Queen Anne’s Lace (Daucus carota). This little bird landed on the nodding stalks, rode them downward and then grabbed a bit of seed – before heading off on its next wild ride.
Though some Canada Goldenrod still stand tall and golden in the Old Fields, many have already begun to seed, making silver plumes in the late afternoon sun.
And the glorious orange Butterfly Milkweed (Asclepias tuberosa) is ripening its seed for next year’s crop inside its long slender ponds.
A Song Sparrow (Melospiza melodia), perhaps finishing its molt, hid in a bush after foraging for fruits in another bush nearby.
Out in the eastern Old Field, the old Black Walnut (Juglans nigra) tree has shed its leaves, one of the earliest trees to do so. This tree left behind a giant crop of walnuts this year. Can you see the small green balls hanging from virtually every bare limb?
Let me show you a bit closer look:
The yellow green, round Walnuts are covered with a leathery surface (exocarp) which turns from bright green to the black that can stain your hands! Botanists refer to walnuts as “drupes” (like apricots and peaches) because the seeds are inside a pit. Raccoons love them and take advantage of this fall abundance to feed their kits, which stay with the adults until late fall. Keep an eye out for them in the Oak-History forest!
Last Sunday, out of the corner of my eye, I spotted an Eastern Chipmunk (Tamias striatus) slipping into the hole under the Bur Oak that was posted here last week – but it was too quick for me! So here’s one I saw popping out of a log at the end of September a few years ago.
Squirrels, chipmunks and other inhabitants of the woods also feast on another drupe – the “nut” of the Shagbark Hickory (Carya ovata). Shagbark Hickory is one of my favorite trees because of its unusual bark which makes it easy to identify. Here you can see the bark and the three stages of the more oval “nut” with its segmented surface (exocarp) as it turns from green to black and the hard pit or endocarp that contains the “nuts,” seeds of next year’s Hickories. Below is evidence last Sunday of some little forest creature having enjoyed a hickory “nut.”
Unhappily, there is also an aggressive, non-native vine producing its late season fruit. The yellow casings split open to reveal a red fruit (arils) inside that contains the seeds. It’s lovely but it’s a killer. Asian Bittersweet (Celastrus orbiculatus) winds around trees and shrubs and literally throttles them; in some cases, its weight can pull trees out of the ground! So please! Don’t plant or pick these vines! They get spread by birds at this season and they also spread by rhizomes under the ground so they don’t need any help from us! In fact, Dr. Ben hopes to find time to get rid of some of these killers this fall.
Seeding got some human help this week, too! Dr. Ben VanderWeide, the OT Stewardship Manager and Catherine Hu, a hardy volunteer, spent a morning clearing non-native invasive Common Privet (Ligustrum vulgare) from an area on the east end of the parking lot.
Ben harvested some seeds of native Bottlebrush Grass (Elymus hystrix) elsewhere in the township and he and Catherine spread them beneath the trees to begin a covering of native plants. We could use more volunteers like Catherine! Check out our “Volunteer Workdays” page under the “Stewardship” tab on the home page for projects to which you could contribute a few hours. Please?
Nature’s Music in the Meadows: Very Small Grasshoppers and Tiny Crickets
Nature seems to always have a sound track and the early fall version features the courting sounds of insects – which is nice just when we’re starting to miss birdsong. As in previous weeks, the lead singers now are the Red-legged Grasshoppers (Melanoplus femurrubrum). These small creatures, just an inch long when fully grown, fill the meadows with their creaking buzz as they court their mates, who then lay their eggs in the ground for next year’s hatch. Right now there are hundreds of them escorting you as you walk the sunny paths through the Old Fields. For a sense of scale, here’s one that was sitting on a closed Queen Anne’s Lace (Daucus carota) blossom on Sunday.
But this week, even tinier songsters hatched in huge numbers along the western side of the park, Ground Crickets (Subfamily Nemobiinae), possibly the common Allard’s Ground Cricket (Allonemobius allardi), but I can’t be sure. Ground Crickets look like the larger black Field Cricket (Subfamily Grylinnae) that is nocturnal, except Ground Crickets are much smaller, less than a 1/2 inch long. But they can sing up a storm by rubbing their wings together! Listen to the high-pitched trill of the Allard’s Ground Cricket at this link.
Odds and Ends: Thwarted Spider Webs, Elegant Wasp Nest, Woodpecker Carpentry and a Late Season Butterfly
A native plant that grows aggressively on any disturbed soil is seeding like crazy right now, but despite that, it won’t come back strongly next year unless the land is disturbed again. Fireweed (Erechtites hieraciifolius) has temporarily colonized the area across the Playground Pond since a lot of non-native plants were removed in the spring. Even when blooming, the height of Fireweed can vary from 4 inches to 6 feet! Right now most of them are very tall and look like this, their fruits (achenes) producing silk (pappus) to carry the seeds through the air.
An unfortunate Orb Weaver Spider near the Playground Pond lost the element of surprise when its web was filled with the silk that Fireweed uses to disperse its seeds.
Over at the eastern end of the Center Pond, you can now spot a huge wasp nest hanging from the tip of a branch over the water. It’s probably the summer home of either Yellow Jacket Wasps or their relatives, Bald-Faced Hornets. These amazing pollinators chew on bits of woods which they mix with their saliva. With that mixture, they create these incredible artworks using just their mandibles and their tiny feet! Don’t be too worried about the hive’s inhabitants at this time of year. The cold nights kill off the whole hive except the fertilized queen who hides in a crevice or under some bark until spring, when she sets off to establish a brand new nest. (Many thanks to an unnamed fellow park hiker for pointing this nest out to me!)
A male Red-bellied Woodpecker (Melanerpes carolinus) worked diligently, hammering away at a dead tree east of the Playground Pond this week. At this time of year, he might be enlarging a hole below last year’s nest to use during the coming cold season. This large woodpecker which has a red cap and nape and barred back is often mistaken for the less common Red-headed Woodpecker (Melanerpes erythrocephalus) whose head is completely red and whose black back has large white patches.
An Orange Sulphur (Colias eurytheme) butterfly fluttered rapidly across the field, searching out nectar from the last blooms of the summer.
And Whose Hatching???
During Goodison Good Times last Saturday (Sept. 19), a mother and child saw baby Snapping Turtles (Chelydra serpentina) hatching near the Center Pond! So exciting! And such a coincidence, since I saw two Snapper hatchlings crossing the Paint Creek trail just a week before, something I’d never seen before! So those eggs in their rubbery shells laid in the soft dirt survived without being eaten by foxes, raccoons or coyotes. Amazing! Here’s the one I saw, about the size of a 50 cent piece!
If autumn comes too soon for you or makes you feel a bit melancholy, as it seems to for many people, it might help to remember that the natural world uses autumn as a time to sow the seeds of next year’s spring. Even as the Black Walnuts shed their leaves and summer flowers fade, native fall flowers burst with color, grasshoppers and crickets sing their mating calls and baby turtles are born. And so, life goes on, endlessly renewing itself.
*Footnote: My sources for information, as well as Oakland Township Stewardship Manager Dr. Ben VanderWeide, are as follows: Ritland, D. B., & Brower, L. P. (1991). The viceroy butterfly is not a Batesian mimic; Stokes Nature Guides: A Guide to Bird Behavior Volumes 1-3, Allaboutbirds.org, the website of the Cornell Ornithology Lab at Cornell University; Wikipedia; http://www.butterfliesandmoths.org; Herbarium of the University of Michigan at michiganflora.net.; various Michigan Field Guides by Stan Tekiela; Butterflies of Michigan Field Guide by Jaret C. Daniels; University of Wisconsin's Bug Lady at www4.uwm.edu/fieldstation/naturalhistory/bugoftheweek/ for beetle info http://www.migrationresearch.org/mbo/id/rbgr.html for migration info, and invaluable wildflower identification from local expert, Maryann Whitman.