Sawflies

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…

Stinkhorns

Stinkhorns are mushrooms that are found from the tropics to more temperate regions such as Wisconsin. They can suddenly appear in mulch, lawns, and areas with bare soil. These visually-shocking fungi get their common name from their characteristic, unpleasant odor. Stinkhorns do not cause plant disease, and can actually be beneficial, as described in this factsheet.

European Pine Sawfly, Neodiprion sertifer

If you’ve noticed masses or writhing, dark green “caterpillars” on your pine trees this spring, you likely have an infestation of European pine sawfly. This insect lives in large colonies, feeding on last year’s needles until they finish their development, then pupate in the soil or leaf litter. To learn more about this pest, read this article…

Phytophthora Root Rot of Christmas Trees

Phytophthora root rot is a common disease of Christmas trees including Douglas-fir, balsam and true firs (e.g., Fraser, balsam and Canaan), spruces, and pines. This fact sheet covers symptoms and management.

Winter Burn

This publication covers winter burn, a common problem of evergreens including those with broad leaves (e.g., boxwood, holly, rhododendron), needles (e.g., fir, hemlock, pine, spruce, yew) and scale-like leaves (e.g., arborvitae, false cypress, juniper) grown in open, unprotected locations and exposed to severe winter conditions.

Woody Ornamentals Pest Management in Wisconsin

Author(s): Chris Williamson, P.J. Liesch, Jim Kerns, Roger Flashinski Woody Ornamentals Pest Management in Wisconsin is an indispensable resource for nursery growers. This completely revised publication identifies pests of trees and shrubs in the state plus the products available for their control. It also notes products that are registered for use by homeowners (56 pages; […]

Scorch and Related Problems in Trees and Shrubs

Author(s): M.F. Heimann, G.L. Worf Scorch, or the browning of leaf edges, affects a wide range of deciduous and evergreen plants throughout Wisconsin, especially ash, linden, maple, oak, pine, and spruce. While scorch is easily recognizable, it’s important to recognize that it is a symptom, not a cause. A number of problems cause symptoms that […]

Root-Knot Nematode

Root-knot nematodes (Meloidogyne spp.) are small, soilborne, worm-like organisms that infect many agricultural and horticultural plants. This publication describes the symptoms, management and control of root-knot nematodes in Wisconsin.

White Grubs on Christmas Trees

P.J. Liesch and R. Chris Williamson, UW-Entomology Revised:  5/20/2013 Item number:  XHT1208 White grubs (i.e., larvae) of the common May/June beetle or “Junebug” (Phyllophaga spp.) are an important pest of Christmas trees in Wisconsin.  This soil-dwelling pest feeds on the roots of pines, firs, and spruces, and can cause damage severe enough to kill small […]

Drought and Watering of Ornamental Plants

Laura Jull, Woody Ornamental Specialist, UW-Extension, UW-Madison Revised:  7/13/2012 Many of our established woody ornamentals can survive periods of prolonged drought. In response to drought conditions, some of our woody ornamentals, both native and exotic, can start the annual fall leaf defoliation a bit early during prolonged drought conditions.  Leaves can also turn brown and […]

Controlling Deer Damage in Wisconsin

Scott Craven, Scott Hygnstrom, Philip Peterson Revised:  1/24/2001 Item number:  G3083 Illustrates numerous methods for protecting crops and other property from deer. Offers designs for deer fences and other constructions, along with a list of repellents and scare devices (8 pages). Download Article

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