Introduction

image of line drawing of Multiflora RoseIn October of 1992, the Missouri Department of Conservation and the Natural Areas Association hosted a workshop for land managers entitled "Managing Problem Exotic Plant Species in Missouri and the Midwest." At that workshop a number of problem plant species were addressed with a focus on effective control measures on public lands. Speakers from throughout the Midwest contributed their experiences and expertise on mechanical, chemical, and biological methods for controlling exotic or native plant species that can cause problems on public or private lands.

The purpose of this manual is to provide land managers a compilation of control recommendations from workshop participants as well as from available published and unpublished material on plant species of concern. The scope of this effort was broadened to include guidelines not only for those species addressed at the workshop, but also for some additional Missouri problem plants for which control methods are documented. The twenty-four guidelines that follow are intended to alert managers to aggressive exotic plants that may require control as well as to give specific recommendations for treatment. Results cannot be guaranteed using the methods given here because of the variability between sites where these plants may occur. We are in the early stages of learning the best treatment methods for many problem species. Nevertheless, managers can save years of experimentation by learning from the successes and failures of others. A list of references is included with each guideline to allow for further study of pertinent literature or to contact other management personnel with experience in controlling particular species.

Although an attempt was made to include most problem plant species currently requiring control in Missouri, there are certainly additional species that will join the ranks of Missouri's problem exotics in the future. These may be aggressive exotics that should be controlled wherever they are found, or they may be native species which are only problems in specific settings where their spread is at the expense of a natural community that should be protected. The following list consists of species not included in this manual that have presented management problems in other states and may create problems in Missouri now or in the future.

Managers should be aware of the potential aggressive spread of these species on public lands, so that, if control becomes necessary, it can begin before the species becomes well-established. recommendations given for the use of herbicides in this manual are subject to label restrictions. By law, herbicides may only be applied according to label directions. The herbicides recommended in this manual are general use herbicides with the exceptions of Tordon 101 Mixture and Tordon K for kudzu treatment. Pesticide application certification is governed by state laws and therefore varies by state. For safety reasons, it is a good idea for persons who will be dealing with even general use herbicides to get pesticide certification, whether required by law or not. In Missouri, certification and recertification classes are taught by the Missouri Department of Agriculture.

This manual is provided as a three-hole-punched manuscript that can be kept in a looseleaf binder and added to as further material is gathered on the species included or as additional species' recommendations become available. It is hoped that this document will be a useful resource for land managers in controlling aggressive exotic and native plant species. Comments are welcome on the recommendations presented here. As managers gain experience with controlling unwanted vegetation, that experience can be incorporated into future revisions. A form is provided at the end of this manual that may be used to submit additional management experience.