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Knowledge Center

Weed Identification Sheets

 

Weed Identification and Control Sheets

Identification and control of invasive species of the Midwest.

Information Sheets

Pest Control & Plant Care

Japanese Beetles:

See our Pest Identification and Control Sheet for Japanese Beetles

Gypsy Moths:

Gypsy Moths are a serious threat to our already stress oak trees. The caterpillar of these introduced moths can be found in such great numbers that they are able to completely defoliate a tree. However, any pesticides used to kill gypsy moth caterpillars will also kill native caterpillars and many other insects as well. Many hundreds of species of native insects live on oak trees or eat their foliage. These insects are critical parts of our ecosystem; for example they are the primary source of food for songbirds as they raise their young. Even “Bt”, a soil bacteria named Bacillus thuringiensis, which is touted as “natural” and non-toxic, will indiscriminately kill any caterpillars of any species feeding on any tree (even non-target plants) in a treatment area. Because of this, we feel that carefully targeted pesticide treatments should only be used as a treatment of last resort for gypsy moths. In the long term there is hope that the gypsy moths' natural enemies and native predators will be able to keep them in check. In the mean time, there is much a property owner can do to protect their oaks. See the following links for more information:

Oak Wilt

We believe that oak wilt is a native fungal infection that has become an epidemic because of our landscape use patterns. Historically oaks were spread out widely in open woodlands and savannas. Today most of our oaks are growing closely together in woodlands with a closed canopy. With the trees growing so much closer together they are more likely to share grafted roots and spread the disease then they would have before settlement. Furthermore, competition from weedy understory trees and invasive brush creates stress on the oaks, making them more susceptible to disease. Finally, intensive land use, especially development causes injury to trees giving the pathogen an opportunity to attack the tree. We feel that woodland restoration is good preventative care for your woodland, but see the following links to learn more:

Emerald Ash Borer

These tiny insects have arrived in the midwest and are starting to kill ash trees in scattered areas, with potential to spread across the entire region. Once this small beetle is discovered, there is little that can be done but to cut down all of the ash trees in that area to slow the spread of the insect. The biggest concern is with the loss of urban trees where ashes have been frequently planted, we would argue, too frequently planted. We recommend that these trees will be replaced with a diversity of hardy native trees thus reducing the impact of any epidemics in the future. Though native to floodplain forest communities, in many of our woodlands these ashes are considered weedy understory trees and are substantially overpopulated, posing a great threat to the continued survival of oaks in our traditionally oak-hickory woodlands. While a reduction of green and white ash trees in some woodlands might, in fact, be ecologically beneficial, we are concerned about the impacts of the ash borer on our less common ash species such as blue ash, black ash and pumpkin ash. If you suspect you find emerald ash borer in Wisconsin or Illinois, you should report it to your local county extension.

Tree and Shrub Pruning

Native plants are often considered too “wild” looking for landscape use. But native trees and shrubs can look just as orderly as traditional landscaping plants with proper pruning and care. Just remember that “less is more” you can always come back and prune more off later, but you cannot put back what you just cut off! For more guidance, see the below websites: