Management Practices for Weed Control in Roadway Right-of-Ways

Project summary:

Managing roadside vegetation is crucial in ensuring motorists' safety because weeds and brush growing in rights-of-way can conceal road signs and other dangerous obstacles. Use of conventional practices (mechanical, chemical, and biological) for management of noxious weeds have been criticized for various inherent limitations, among which is their negative effects on development of native vegetation. Problems associated with management of noxious weeds along roadside rights-of-way are compounded by the patchy nature of weed distribution. Accurate application of control measures is difficult, necessitating uniform, often indiscriminate application over infested areas. Precise application of the management practices would be possible if location of the noxious weeds could be accurately determined within the large highway right-of-way area (over 260,000 acres) under MnDOT's management. In this research project, weed population distribution data will be analyzed to assess the accuracy of subsampling at estimating weed population distributions. Data collected will come from a four-year survey carried out by MnDOT District 4 staff. Conclusions regarding these data will be used to design a field survey experiment for 2005 to validate recommendations related to subsampling intensity. Weed population models will be selected and tested to assess their ability to predict the spatial and temporal distribution of weeds within roadway rights-of-way. A user's manual giving instruction on how to perform weed surveys and manage weed population data via GIS databases will also be produced.