Fall is the time of harvest here in the Midwest. Golden stacks of hay bales, farmer’s markets teeming with end-of-season produce, and above all, apples. But step away from the orchard and into an oak woodland and you’ll find a different kind of autumn apple: an oak apple gall. What looks like a small, lime-green, spotted apple dangling from an oak leaf is not a fruit at all, but rather a secret abode for a tiny wasp.
There are more than 50 species of oak apple gall wasps in North America. Each one creates a unique fruit-like structure that protects and feeds its eggs and larvae as they develop. Lately, I’ve been finding many dried, spent brown husks created by the larger empty oak apple wasp (Amphibolips quercusinanis) around the Lake County Forest Preserves in northern Illinois.
The dog days of summer are a bounty for the senses. We see the lemon-yellow of whorled sunflower blooms, taste the ripe flavor of a homegrown tomato, smell the spicy sweetness of bee balm flowers, feel the heat of the day and the cool of the evening. Yet the most quintessential sensation of these end-of-summer days is hearing the overwhelming cacophony of cicada songs around the Lake County Forest Preserves in northern Illinois.
Around the first frost is the best time for spotting bears in the Lake County Forest Preserves in northern Illinois…woolly bears, that is! These fuzzy caterpillars succumb to a late fall wanderlust and can often be found traversing trails and roads, as well as climbing vegetation and nibbling a last few bites before winter sets in. They belong to the subfamily Arctiinae, commonly known as tiger moths. Their scientific name stems from the ancient Greek word arktos (“bear”), for the appearance of their hairy larvae.
The sun had set, the campfire was doused, and the food was stashed away for the night as my sons and I tucked ourselves into our sleeping bag cocoons, thoroughly exhausted in a way one can only be from a day spent entirely outdoors. Still, sleep would not come easily. The whirling drone of thousands of annual cicadas buzzed through the nylon walls of our tent loud enough to overpower our fatigue. I lay awake, thinking it odd the cicadas would be calling after dark, when I caught a hint of the rising full moon through the ceiling screen and realized they were staying up late to party with the extra light. One of my boys groaned, “Isn’t there anything that can stop these CICADAS?” As a matter of fact, the next day we found just the thing: a cicada killer wasp (Sphecius speciosus).
Late spring and early summer are busy seasons for children visiting the Lake County Forest Preserves for pond study programs. The shorelines of ponds pulse with the excitement of students, nets in hand, ready to discover the macroinvertebrates teeming under the water’s surface. The most delightful find this season by students has to be what Henry David Thoreau once called the “submarine cottages” of caddisfly larvae.
At a recent Firefly Campfire at Ryerson Conservation Area, kids and adults alike were flitting around, as fast as the fireflies they were trying to catch. For many of the children, this was their first time experiencing the age-old summer tradition of capturing living light. While the woods that night sparkled like the fourth of July, many of the adults lamented that their yards didn’t have many fireflies—certainly not like the numbers they remembered chasing as children. Turns out they may be on to something.
Widespread anecdotal evidence of these dwindling evening displays have prompted scientists to take a look at possible reasons. One big culprit to the demise of these bioluminescent beetles seems to be the one thing that makes them so special: light. Continue reading →
Our adventure to traverse the entire length of the Des Plaines River Trail continued with our trek from Kilbourne Road to Independence Grove Forest Preserve under the shining sun and heavy air of late summer. The air was heavy not only with humidity, but with the calls of cicadas, tree crickets, and katydids melding into a three-part harmony that signaled the end of summer. The air was also pregnant with the perfume of flowering plants. It was clear that this hike belonged to the bugs and blooms. Continue reading →
My family went on a bike ride last weekend at Ray Lake Forest Preserve. All afternoon, rain sputtered on and off as the clouds played tag with the sun. After climbing up a steep hill, the sky darkened again and we sought refuge under a canopy of large oak trees. One of my sons yelped,”Ouch! That raindrop hurt!” We quickly realized it wasn’t a raindrop, but a storm of acorns jiggled loose by the wind, plopping down on us. The trail became littered with acorns, and the kids began grabbing them. Upon inspection, the boys noticed tiny round holes in many of the acorns—evidence that these nuts were homes to acorn weevils (Curculio spp).
As summer winds down, a telltale hum that signals the changing seasons begins to ramp up in the fields and forests. These trills and chirps are the mating calls of tree crickets (Oecanthinae)—a group of fascinating insects that are often heard but seldom known or seen. Their small size and mint green color helps camouflage them amidst the verdant grasses, shrubs and trees of late summer.
Many years ago, while hiking through a prairie at dusk, I saw a stalk of delicate white flowers. They seemed to rise and hover above the surrounding plants like a group of little dancing ghosts. This was the first and last time I ever saw an eastern prairie fringed orchid (Platanthera leucophaea). Due to its dwindling numbers and hidden habitats, this rare plant has reached almost mythical status—a holy grail of sorts in the Midwest. We’re thrilled that this endangered native orchid seems to be gaining a foothold in the Lake County Forest Preserves, which are home to some of the largest remaining populations. Just this month, one of our restoration ecologists discovered an orchid in bloom (photo below). It was found at one of the preserves known to provide habitat for this species but is the first documentation of a population at the site.