This week in the woods, we’ve been finding flies smooshed to the underside of tree leaves. This is the gruesome work of a parasitic fungus. Although not well understood, the process appears to start with a fungal spore invading the fly. The fly lands on a leaf, and the fungus binds its prey with extra-strength hyphae. You can see a second photo, and find an additional link describing fly-death-by-fungus here.
Song sparrows are common birds of forest clearings (for example, around beaver ponds) and they also pop up in shrubby fields. The birds have a look-alike – Lincoln’s sparrow. Here’s a species profile from Cornell that helps distinguish the two species, and a sampling of song sparrow calls from Cornell’s Macaulay Library.
Suddenly, dainty American copper butterflies are swarming the meadows. Despite the name, according to Larry Weber in Butterflies of New England, the insect “may have been introduced from Europe during colonial times, but there’s no way to be sure.” The American copper is one of many butterflies that look completely different depending on whether viewed when their wings are open or shut. For a look at the pumpkin orange coloring of the butterfly’s inside wings, check out this link.
There are two almost identical wild roses blooming now, Virginia rose (pictured) and Carolina rose. It’s probably best to stop at “wild rose” and declare victory – distinguishing the species involves nitty gritty assessments of thorn shape and the shape of the stipule on the leaf stalk. According to the Native Plant Trust, Virginia rose likes dry habitats – so it must be enjoying our recent weather.
Canadian tiger swallowtails are very active now, chasing each other around the woods and visiting gardens. These insects also have a look-alike (this seems to be the theme of the week) in the eastern tiger swallowtail, but fortunately Bryan Pfeiffer has sorted the two species out in this post on his website. One helpful hint from that post: although individual butterfly markings vary, Canadian tigers typically have a continuous yellow band on the forewing.
Hay-scented fern is abundant and often crowds out other plants. It’s also sticky; if a dog accompanies you on your woods walk, you probably are familiar with its tendency to gum up fur. As explained in this Outside Story article, the stickiness comes from “tiny, glandular hairs” that may also deter deer browsing…and thus help the plant along its path to world domination.
Hairy woodpecker chicks have fledged and are focusing their efforts on harassing their parents for food. One way to distinguish juvenile from mature birds is that the young have big red patches covering most of the top of their heads (not to be confused with the red napes of adult males). Hairy and downy woodpeckers look very similar, but hairies are bigger, with distinctively longer bills. Here's an Outside Story article by Doug Morin that describes the two bird species’ differences.
Back on the topic of ferns – you may notice odd little balls at the tip of ferns, wrapped together in what appears to be spider silk. These are the feeding shelters of moth larvae, specifically moths from the genus Herpetogramma. They’re fun for kids to “unwrap” – look for the little green caterpillar in the center (along with kid-pleasing insect poop). Here’s a YouTube demonstration, and a research paper abstract with more details about the moths.
Finally, this week we’ve noticed the fringy blooms of water avens, a plant that grows on the edges of wetlands. It’s not a particularly showy flower, but at a time when most of the woods has turned dark and green, it stands out. Here’s a profile from The Native Plant Trust.