Two view of a Unicorn Caterpillar, which I found munching on a blueberry leaf one fall.
Observed mating on a dogbane plant, their usual habitat:
I spotted this lone caterpillar on a small elm tree in late May 2013.
This moth posed on the leaf of a sweet potato slip in the greenhouse one morning in late May. This isn’t a species we see often, but its coloration was stunning, so I had to grab the camera. We finally figured out the ID when we spotted a pinned specimen in the collection of the Enns Entomology Museum. For more info on this species, see this post on the MObugs blog.
Squash bugs are one of our more problematic pests of cucurbits, particularly summer and winter squash and (usually to a lesser extent) cucumbers. Damage occurs from direct feeding injury, and in addition, squash bugs can serve as a vector for plant disease. Squash plants often decline rapidly when squash bug populations boom.
This is an adult:
Females lay clusters of eggs on plant leaves, usually on the cucurbit plants where the young will feed. Very recently laid eggs tend to be pale in color, such as these:
Eggs turn to a darker shade of red/brown as they get closer to hatching. Most of the time, eggs are laid on the underside of leaves, as shown here:But sometimes eggs are on the upper leaf surfaces, as shown below on a large squash leaf, which provides a sense of scale. Learning to spot the eggs is useful, because physical removal of the eggs is one of our preferred control options to keep population numbers in check. Eggs are vulnerable because they’re not mobile, and we can systematically work our way through a squash planting looking for and squashing the eggs. Eggs take 10 days +/- to hatch (depending on what source you believe; we don’t have our own data for this).
Here are some nymphs that have just hatched:
After a molt, nymph coloration changes to grey, and several more molts take place before adulthood.
Then as adults, the whole cycle begins again:
During the growing season, we most often find adults hanging out along the base of the main stem of the squash plant, close to where the stem emerges from the ground. Another favorite hideout is on the underside of large squash leaves that are touching the ground. When searching for eggs, we also seek out adults & nymphs and squish those, too. The smell of a squished squash bug is rather unpleasant.
During the winter, we’ve found adults taking shelter in weed piles and straw bales, often in the vicinity of the late summer squash planting.
Toads are confirmed predators of squash bugs. In late summer of 2012, I watched an American toad eat an adult squash bug. The squash bug virtually crawled across the toad’s nose. The toad seemed to wait for just the right moment, then, gulp, it was gone. Hooray for toads.
Appropriately named, Giant Swallowtails are the largest butterflies at Chert Hollow Farm (& in Missouri).
More info available from MDC.
These orange-and-black net-winged beetles (Family Lycidae) are not uncommon at Chert Hollow Farm. This is a good example of a species that we see with moderate regularity but know very little about. This photo was taken on an okra plant in July 2012.
A close look is required to identify this insect as a beetle, because we also occasionally see a moth species that is a mimic. The segmented antennae identify this as a beetle.
A spectacular moth; this is the male. This is not a species that we encounter very often. In fact, the one in the photo is the first adult that we’ve seen at Chert Hollow Farm. I found this moth on the ground in the orchard in late May 2012 while doing some hoeing. I saw a flash of color and was relieved when I discovered the hoe had not damaged him. The day was rarely cool for 2012, so the moth was moving slowly, and I couldn’t resist taking a break for a photograph.
We found this caterpillar in August 2011:
Tiger Swallowtails are common butterflies at Chert Hollow Farm.
This individual made its way into our greenhouse but couldn’t figure out how to get out. So in the cool morning, when it was moving slowly, I took it out of the greenhouse (minimizing contact with the delicate wings) and snapped a few photos.
Hornworms of the genus Manduca can be a major pest of tomato plants. Contrary to the claims of this Mother Earth News letter, hornworms can and do eat the fruit of tomato plants. Our hornworm population was happy to provide photographic opportunities to set the record straight, as we did here.
The species shown here is Manduca sexta, which (according to reference books) goes by the common name of Tobacco Hornworm, even though this is the species that we invariably find on our tomato plants. (This is confirmed in David L. Wagner’s excellent book, Caterpillars of Eastern North America.)
To minimize hornworm damage, we pick them off by hand and smush them with a boot. The trails of droppings are often the first sign that these well camouflaged moth larvae are present.
The photo below shows what hornworms are capable of doing to a tomato planting if populations are left uncontrolled. We didn’t check on this planting for about a week and a half before taking this photo (due to family visits, the fact that this is a winter-keeping variety of tomato that doesn’t need to be harvested until later in the fall, and the slightly out-of-the-way placement of the planting since it was being isolated for seed saving).
In early fall 2013, I “adopted” a Tobacco Hornworm so I could watch its life stages. Having to feed it indoors gave me even more appreciation of just how much one can eat! In October, it formed its pupa:
I kept the pupa in a pot of soil indoors over the winter. In April or May, I unearthed it to check on it. Twitching of the pupa upon contact convinced me it was still alive. I kept an eye on it, and in the days prior to emergence of the adult, the color noticeably darkened and shriveled slightly. This photo was taken on the morning of emergence (on May 27):
It emerged sometime that afternoon, but I missed the actual event.
Here’s the recently emerged adult: