Early Summer Scenes
Howdy, BugFans,
Well, the sun has solsticed, and it’s all downhill from here. Our pre-Christian, Germanic ancestors, who were more intimately attuned to the rhythms of the sun, correctly celebrated the winter solstice, aka Yule (which may have come from the Norse word houl, which referred to the sun as the wheel that changed the seasons). They recognized that the winter solstice marked a turning point that would lead to longer, warmer days.
In the BugLady’s neck of the woods, the insect world is dominated these days by mining, sweat, and bumble bees and by lots of flies, including a big hatch of mosquitoes that timed their appearance to coincide with the Riveredge Butterfly and Dragonfly count (causing the BugLady to move along the trail rather smartly). Here’s what she’s been seeing in the run-up to summer.
STILT BUG ON FERN: This started out as a fern fiddlehead picture – the BugLady did not see the stilt bug when she took the picture, it was one of those happy surprises that photographers get when they put an image up on the monitor. Most stilt bugs/thread bugs are plant-eaters that supplement their diet of plant juices with the odd, small invertebrate. Some are more “meat-oriented,” and one species is used to control Tobacco hornworms.
CRAB SPIDER: A friend of the BugLady’s recently asked where all of the beautiful, plump crab spiders are. They’re here, but they have some growing to do.
KATYDID NYMPH: And another friend, from Southern climes, asked if the BugLady was seeing katydids yet. Same answer.
TIGER BEETLE: The BugLady loves seeing the flashy, green Six-spotted tiger beetles. Usually they perch on a bare path, wait until you get too close, fly ahead of you about a foot above the ground, land, and repeat the process when you get too close again. Until this year, the BugLady had never seen one off the ground, but she’s photographed three in the past month. Get to know Wisconsin’s tiger beetles at https://wisconsinbutterflies.org/tigerbeetle.
MILLIPEDE ON RUST: Millipedes are decomposers/detritivores, feeding on dung, plant juices, and pieces of dead plant materials like decaying leaves, breaking them down for organisms even smaller than they are. Some like fungi.
If you’ve seen the invasive shrubs Glossy and Common buckthorn, you’ve probably seen stems and petioles with a bright orange blob on it. The blob is a rust – a fungus – called Crown rust (Puccinia coronata). Buckthorn is one of its hosts, and the alternate hosts are a variety of grasses, including agricultural crops like oats and rye. If you see grass leaves with thin orange streaks on them, you’re probably seeing a variety of crown rust. Crown rust has a complicated life cycle (http://www.minnesotaseasons.com/Fungi/Crown_Rust.html ), but the bottom line here is that the rust on buckthorn releases its spores in a soupy, sweet liquid that attracts insects, and the insects carry the spores to rust patches on other buckthorns and fertilize them. The rust probably doesn’t get much bang for its buck when its spores are eaten by a short-legged pedestrian like a millipede.
BALTIMORE CHECKERSPOT CATERPILLER: The astonishing Baltimore Checkerspot https://bugguide.net/node/view/1771510/bgimage and https://bugguide.net/node/view/1636206/bgimage, and its caterpillar, is one of the BugLady’s favorites. This caterpillar hatched last summer and munched on its host plant (historically white turtlehead, but in the past 50 years, they’ve adopted Lance-leaved/English plantain, and those are the only two plants a female will oviposit on). It overwintered as a caterpillar, woke up hungry this spring, and looked around, – no turtlehead in sight yet – so it’s been eating a variety of plants, especially white ash. Both turtlehead and plantain leaves contain poisonous glycosides (turtlehead has more), allowing the caterpillar and butterfly to get away with their gaudy colors. And remember – the butterfly (and the oriole) get their names not because they were discovered in that city, but because 17th century English nobleman Lord Baltimore, a familiar figure to the colonists, dressed his servants in orange and black livery. Get to know Wisconsin’s butterflies at https://wisconsinbutterflies.org/butterfly.
MONARCHS: Most of the Monarchs that return to Wisconsin are probably Gen 2 – the second generation north of their wintering ground in Mexico. There ensues two short-lived generations – Gen 3 and 4 – whose only job is to increase the population, and these two clearly got the memo. Gen 5, produced in August, is the generation that is signaled by both waning day length and the lowering angle of the sun to migrate instead of reproducing (though there always seem to be a few that didn’t get that memo).
BEE ON LEATHERWOOD: At a quick glance, you might think that this is a bumble bee, but bumble bees have hairy butts. The BugLady thought this was a carpenter bee (which have shiny butts), but now she thinks it’s one of the larger mining bees in the genus Andrena. Leatherwood is a spring-blooming shrub in woodlands – those fuzzy bud scales protect the bud from chilly spring nights. It gets its name from the fact that its branches can’t be torn off the shrub, and from its strong bark fibers, which were woven into baskets, bowstrings, ropes, and the cords that lashed together canoe frames. Settlers used its branches when they took their children to the woodshed. All human use of it is problematic, because its caustic bark raises some serious blisters.
ROBBER FLY: Another bumble bee look-alike. Bumble bees eat nectar and collect pollen to feed their larvae; robber flies are carnivores. Laphria thoracia (no common name) can be found on woodland edges from the Mason-Dixon Line north into the Maritime Provinces and west through the Western Great Lakes. Adult Laphria thoracia eat bees and adult beetles (this one has a clover weevil, but the BugLady recently photographed one with an assassin bug), and their larvae feed on beetle larvae in decaying wood. Get to know Wisconsin’s robber flies at https://wisconsinbutterflies.org/robberfly
GOLD-BACKED SNIPE FLY: June is the only month to enjoy these dramatically-colored flies that perch low in the vegetation in moist areas.
SWAMP MILKWEED BEETLE: The BugLady loves finding these “ladybugs-on-steroids.” They’re often tucked down into the axils of the milkweed leaves, and when they see company coming, they either duck down deeper into the crevice or they default to the typical escape behavior of an alarmed leaf beetle – they tuck in their legs and fall off the plant. Their bright (aposematic/warning) colors tell potential predators that they are toxic, due to the milkweed sap they ingest, but damsel bugs, stink bugs, and flower/hover/syrphid fly larvae prey on them nonetheless. For the full (and fascinating) Swamp milkweed leaf beetle story, see https://uwm.edu/field-station/swamp-milkweed-leaf-beetle/.
ICHNEUMON WASP: Every year, large and colorful Therion (probably) Ichneumon wasps drift through the vegetation in perpetual motion, legs dangling, taunting the BugLady https://bugguide.net/node/view/739675/bgimage. They often occur in wetlands, and the BugLady swats mosquitoes and deer flies as she waits for them to show their faces. Which this one did.
Experienced BugFans are saying, “But, but, but – where are the dragonflies?” Tune in next week.
Go outside – look for bugs.
Kate Redmond, The BugLady
Bug of the Week archives:
http://uwm.edu/field-station/category/bug-of-the-week/