If you happen to notice a ¾” to 1 ¼”- long, brown kidney-bean-shaped or round structure on a blueberry bush this time of year, you’ve come upon the blueberry stem gall – a summer and winter home for a dozen or so wasp larvae that will pupate and emerge in the spring as very small (less than 1/8”) black wasps (Hemadas nubilipennis). Last summer a female wasp laid her eggs in a tender, developing blueberry shoot. She then climbed to the tip of the shoot and stabbed it repeatedly, causing considerable damage. Within two weeks the eggs hatched, and the larvae began feeding, which, along with the egg-laying, stimulated the formation of the gall. Initially a blueberry stem gall is green and spongy; by fall it turns red, and by late autumn, it is brown and woody. Next summer, look for multiple holes in these galls that were chewed by the exiting wasps.
What happens to insects this time of year? A few remain active, such as snow fleas, and some, like monarch butterflies, migrate, but the vast majority of insects overwinter in New England. The insects that stay here are susceptible to freezing due to the fact that they cannot control the temperature of their body. Some insects, such as woolly bear caterpillars, can tolerate having ice form in their tissues, but most insects go into a state known as diapause. When the days start getting shorter, these insects reduce the water content of their body, as water freezes at a high temperature compared to other liquids, and replace it with glycerol, which acts like antifreeze, protecting them from freezing. (Due to technical problems which hopefully will be resolved soon, I am unable to include a photograph with this post. My sincere apologies.)
There are basically two groups of wasps: 1) social wasps, such as hornets, yellowjackets and paper wasps and 2) solitary wasps, species that live solitary lives and typically hunt prey for their larvae (the adults consume nectar). Mud daubers are a type of solitary wasp. Organ Pipe Mud Daubers builds cell out of mud in which they put prey (usually spiders) that they have stung and paralyzed, but not killed. They then lay an egg on top of the spiders, and seal the cell. After the egg hatches, the larval wasp consumes the still-fresh spiders, pupates, emerges as an adult wasp and chews its way out of the cell. In this picture a female Organ Pipe Mud Dauber wasp has collected a ball of mud and is applying it to the most recent cell she is making. The name “organ pipe” comes from the shape of the “pipes”, which consist of several cells, placed end-to-end, with the most recent cell at the bottom. (Notice the new, wet mud is darker in color.)
A weevil is a type of beetle whose mouthparts are formed into a long snout, with one antenna on either side of it. The snout is used not only for feeding but also for making cavities in buds, fruits, seeds, stems, and roots of plants, where eggs are laid. When the weevil larvae emerge, they feed within the plant. There are 60,000 species of weevils, all of which are herbivorous and most of which are less than ¼ ” long. The species of weevil in the photograph was on many of the black-eyed Susans that were blooming in an unmowed field, and all of them appeared to be feasting on pollen. Many weevils are pests of plants such as cotton, alfalfa and wheat. You may have even found them inside your house devouring your cereal or flour.
At the risk of boring readers, I wanted to include one final Leafcutter Bee post, showing the two basic shapes that these bees chew out of leaves in order to make their incubator/nursery cells. There are oblong pieces, roughly an inch long, as well as perfectly round, ¼-inch diameter pieces. Each cell consists of several layers of oblong pieces rolled lengthwise which are sealed at one end with a round piece of leaf. The round end pieces appear to be glued into place (perhaps with the pollen/nectar mixture?) at one end of the cell, leaving the opposite end open. The cells are arranged end-to-end, with the open end of the cell placed against the sealed end of the next cell. Together they form a nest that is somewhat cigar-shaped and is typically located a few inches down in the soil, or in a cavity.
The next time you’re in a field, stop and take a close look at a few of the grasshoppers you find there. Chances are great that you will see tiny, red mites on some of them. These Red Grasshopper Mites, close relatives of ticks and spiders, go through three stages: larva, nymph and adult. The larvae (6-legged) attach to the base of a grasshopper’s wings, where they suck the grasshopper’s blood. The nymphs and adults (both 8-legged) are free-living and feed on grasshopper eggs. Each Red Grasshopper Mite nymph requires more than two grasshopper eggs to become an adult. An adult male Red Grasshopper Mite requires three grasshopper eggs for reproducing, and each female, seven to eight eggs. After breeding, a female mite deposits up to 4,000 eggs. Entomologists believe that mites reduce grasshopper survival and reproduction dramatically.
Beaverpond Baskettail dragonflies have an early flight season, first appearing in May in the Northeast. The males (pictured) cruise over the water (often beaver ponds, hence their name) as well as the shore in sexual patrol flight, flying back and forth over the same area repeatedly. After mating, the female accumulates a large egg cluster at the tip of her abdomen, and as she drags it along the surface of the water, a long string of eggs is draped over plants. Once these strings expand, they can be several feet in length and an inch or more in diameter.