Herbaceous perennial weeds are common pests in agricultural production systems. Plants with this life history have proven to be especially competitive as they have the ability to regenerate from perennial organs that persist belowground. This trait allows plants to tolerate management methods, compete with other plants, and survive stressful growing conditions. These traits can cause significant reductions in crop yield and may account for why herbaceous perennial weed species are increasing in frequency throughout Canada, the Midwestern United States and Wisconsin.

Herbicides, mowing, tillage, burning, seeding competitive plants, and biological control have been effective in managing perennial weeds if applied correctly. Management methods typically target reducing stored resources in perennial storage organs and shading of shoots. Often combining techniques that integrate both strategies work the best. Due to the range of species biology and phenology, no recommendations are effective across all weed species. Often, it is useful to determine if perennial weeds are simple or creeping perennial weeds as biology and spread have subtle, but important differences for each life history. Correct identification of this type of life history is also useful in selecting the appropriate management methods. Below is a summary of biology, spread, and general management recommendations for simple and creeping perennial weeds along with a table of common perennial weeds found in Wisconsin. This presentation will provide an overview of the biology of perennial weeds and important factors to consider when using a range of management methods for these weed species.