Abnormal plant growths called galls come in all sizes and shapes, are found on leaves, buds and stems, and are caused by a number of agents, including insects. A majority of insect galls are caused by the eggs and developing larvae of flies, wasps and midges. Jewelweed, or Touch-Me-Not (Impatiens capensis), has a very distinctive looking aborted bud gall that is produced by a midge (Schizomyia impatientis). While some galls provide shelter and food for a lone resident, the Jewelweed Gall Midge is colonial, and several orange larvae can be found residing in separate cavities within the gall. These midge larvae are now emerging and will overwinter as adults.
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Twenty minutes of observing air-borne visitors to a patch of roadside Chicory revealed nine different species of pollinators, including bees, flies and beetles. Most of the insects were bees, which makes sense, as honeybees, leafcutting bees and ground-nesting bees are the primary pollinators of this flower. Without exception, all of the pollinating insects were covered from head to toe with Chicory’s white pollen grains. As they circled the flowers’ stamens collecting pollen, the insects’ bodies were inadvertently dusted with some of it. Thanks to these diligent pollen-collectors and transporters, American Goldfinches and other seed-eating birds will be feeding on Chicory seeds come winter. (Electron microscopy by Igor Siwanowic and Scienceworks.)
There is no way you can walk by the fruiting body of Pseudocolus fusiformis, a member of the Stinkhorn family Phallaceae, without noticing it. Its shape is markedly different from most fungi, in that it has three or four separate orange “arms” which are fused at the top. If your eyes don’t detect it, your nose most certainly will. Also known as “Stinky Squid,” this fungus emits a strong, putrid odor which comes from the dark green, spore-bearing slimy material (gleba) that is found on the inner surfaces of the arms. This smell attracts insects, primarily flies, which inadvertently disperse spores after visiting the fungus. Look for round egg-like whitish structures at the base of Pseudocolus fusimormis – these are young fruiting bodies that have yet to develop arms. (Thanks to Shiela Swett for photo op.)
Galls are abnormal plant growths that can be caused by insects, fungi, bacteria, nematode worms and mites. Insects cause the greatest number of galls and induce the greatest variety of structures. Galls provide both food and shelter for the organisms living within them. Galls develop during the growing season, often in buds and on leaves. Pine Cone Willow Galls, named for their resemblance to small pine cones, are found on willows, typically in terminal buds. A gall midge (Rhabdophaga strobiloides) is responsible for the willow bud going haywire and developing abnormally. (No-one has determined exactly how insects cause galls, whether it’s the act of laying eggs in or on the plant, or if it’s somehow connected to the chewing of the larvae into the plant.) Each gall-making insect has a specific host plant, or small group of related plant. The galls that each insect species induces and lives in while developing into an adult has a recognizable shape and size. When you think you’re seeing pines cones on willow trees, you’re not hallucinating, you’ve just discovered the temporary home and food supply of a tiny fly, known as a midge.