Goldenrod Gall Fly, Eurosta solidagnis

You’ve probably seen spherical swellings on goldenrod stems at one time or another, but do you know what caused those? A type of small fly with patterned wings is responsible for the most common gall on goldenrods. To learn more about the goldenrod gall fly and how it creates those golf ball-sized growths, read this article…

Silver spotted skipper, Epargyreus clarus

Skippers are a group of small butterflies with quick, darting flights. The silver spotted skipper is one of the largest skippers. This chocolate-colored butterfly is easily identified by the conspicuous white or silver spot on the underside of its hind wing that gives it the common name. Read about this common, but often overlooked butterfly, in this article…

Black swallowtail, Papilio polyxenes

If you’ve seen a large, mostly black butterfly lately, chances are it was a black swallowtail, a very common butterfly of eastern North America.  The colorful caterpillars feed on many herb garden plants while the adults nectar at a variety of flowers. To learn more about this species and how to encourage it in your garden, read this article…

Beetles (Coleoptera)

The beetles are the most numerous group of insects, with both pest and beneficial species.  Regardless of whether they are plant feeders, scavengers, or predators, the adults all have the first pairs of wings hardened into sheaths that cover the abdomen. To learn about some of the most common types of beetle, read this article…

Maple and Other Trees Disorder: Cottony Maple Scale

Author(s): C.F. Koval, D.L. Mahr, P.J. Pellitteri Cottony maple scale is an insect that can infest the twigs of maples and other shade trees with popcorn-sized cottony masses. These masses produce a considerable amount of sticky liquid that resembles tree sap and eventually turns black due to fungal growth. Infestations are usually more severe in […]

Deciduous Tree and Shrub Disorder: Skeletonizing by Rose Chafer

Author(s): R.C. Williamson, C.F. Koval Skeletonizing of the leaves of roses, raspberries, grapes, fruit trees, and many other cultivated trees and shrubs may be caused by the adult rose chafer, Macrodactylus subspinosus (Fabricius). Adult beetles are attracted to flower blossoms, particularly roses and peonies. Damage occurs in June and tends to be most severe in […]

Iris Borer

Iris borer is the most serious pest of iris in Wisconsin. Iris plants attacked by iris borer will discolor, wilt, and die during late June and July. On close examination of affected plants, a pinkish-white caterpillar can be found feeding on the inside of rhizomes. This factsheet covers identification and control of this serious pest.

May/June Beetles

May/June beetles or “Junebugs” (Phyllophaga spp.) are beetles in the family Scarabaeidae. These native insects are common throughout Wisconsin and can often be seen flying near lights or heard hitting window screens on early summer evenings. Learn more about these large beetles and their larva, found in the soil, in this factsheet.

Insect Pest Management for Greenhouses

This handy chart lists pesticides that are most effective against common greenhouse pests such as aphids, scales, leafminers, spider mites, and thrips. Formulation, effectiveness, cautions, and other details are provided.

Professional Guide to Emerald Ash Borer Insecticide Treatments

A variety of insecticide products and application methods are available to professionals for control of the emerald ash borer (EAB).  Since the presence and infestation level of EAB is quite difficult to determine at early stages of an infestation, insecticide treatments may be merited to mitigate damage by EAB.  However, not all ash trees should be treated as some may be too extensively compromised or in poor condition to receive treatment.

Black Cutworm

Karen Delahaut Revised:  8/6/2012 Item number:  A3821 Black cutworm larvae are active nighttime feeders, clipping many seedlings at or below the soil line. They prefer beets, carrots, cucumber, leafy greens, melons, peas, potatoes, pumpkins, snap beans, squash, and sweet corn. If not controlled, they can destroy roughly a third of a planting. Find out when […]

Caterpillar Pests of Cole Crops

K.A. Delahaut Revised:  8/6/2012 Item number:  A3724-E This fact sheet covers the imported cabbageworm, the cabbage looper, and the diamondback moth. Scouting tips and effective means of control are highlighted.   Download Article

Support Extension