Common Milkweed Insects

Almost everyone knows that monarch butterfly caterpillars live only on milkweeds, but did you know there are many other insects that feed exclusively on these plants? From other caterpillars to bugs and beetles, there are several types of insects that have developed ways to avoid being affected by the toxins in milkweeds and have become specialized feeders on these plants. Lean more about some of the most common insects found on milkweed in this article…


The buzzing of cicadas means it’s the height of summer. In Wisconsin there are only a few species of this group of insects that is mainly tropical in distribution. Feeding underground on roots for years as nymphs, the adults are only around for a few weeks, making their distinctive noise and laying eggs for the next generation. Learn more about these insects in this article…

Blueberry Maggot

Blueberry maggot was first detected in Wisconsin in the summer of 2016, and is expected to eventually have a significant impact on blueberry production in Wisconsin. This pest feeds inside blueberry fruit causing it to become soft as it develops. This factsheet describes symptoms, the insect’s lifecycle, monitoring strategies and management methods.

African Fig Fly – Pest Alert

Pest Alert Authors: Janet van Zoeren and Christelle Guédot, UW-Madison Entomology Last Revised: 04/17/2019 X-number: XHT1267 The African fig fly (AFF), Zaprionus indianus, is an invasive vinegar fly closely related to flies in the genus Drosophila [which includes the common vinegar fly (also sometimes called the common fruit fly) and spotted-wing drosophila (SWD)]. AFF is […]

San José Scale

This factsheet describes the symptoms, life cycle, monitoring methods and control of San José scale (Diaspidiotus perniciosus). This fruit tree pest can be found in most fruit growing regions of the United States. In well-managed orchards, populations of San José scale are generally too low to cause economic damage. In poorly managed orchards however, San José scale can get established and be difficult and expensive to control.


Katydids are one of the many creatures buzzing, trilling and chirping away in the summer night insect chorus. These cricket and grasshopper relatives are fairly large insects, but often overlooked because they come in colors and shapes that blend in with their environment to prevent predation. Learn about the main groups of katydids and some interesting facts about these plant-eating insects…

Damsel Bugs, Family Nabidae

You likely have some beneficial predators in your garden that you’ve never paid attention to. Damsel bugs are slender, tan-colored bugs that look a lot like assassin bugs or other plant bugs that feed on plants. But all of the damsel bugs, or nabid bugs in the Family Nabidae, are predators. To learn more about this good guy that eat aphids, caterpillars and more, read this article…


Sawflies are a group insects related to wasps that get their common name from the saw-like appearance of the ovipositor, which females use to cut slits in stems or leaves to lay their eggs. The plant-feeding larvae often look like caterpillars or slugs, and many are quite noticeable because they often stay together to feed in groups and quickly cause noticeable defoliation on their hosts. Learn more about sawflies in this article…

European Chafer

A serious insect pest of turfgrass, the European chafer beetle was first reported in Door County, Wisconsin in 2016. European chafer grubs voraciously feed on turfgrass roots and cause thinning, wilting, and irregular patches of turf that can easily be pulled back or rolled up from the soil. This fact sheet details the life cycle of the European chafer and offers insecticide recommendations for grub control.

Spotted Lanternfly

Spotted lanternfly (SLF) is an invasive planthopper native to China, India, and Vietnam. It was first detected in the U.S. in Pennsylvania in 2014, and due to its highly invasive nature, it appears to be spreading rapidly. SLF has a large host range and potentially could greatly impact the grape, tree fruit, plant nursery and timber industries in the U.S. Learn about what to watch for with this new pest.

Praying Mantids

The praying mantids are a group of insects with very characteristic front legs designed to capture and hold prey. The common name comes from the way the legs are held upright when hunting, but they don’t really have any religious affiliations. To learn more about these fascinating predators, read this article…

Common Columbine Pests: Columbine Leafminer and Columbine Sawfly

If you have columbines in your garden, you likely have seen squiggly white trails or blotches on the leaves or had the entire leaf devoured at one time. These are significant as cosmetic problems, but generally have little impact on the plant’s health. Learn more about the life cycle of the two insects that cause these problems and how to deal with them in this article…

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