How do OHVs contribute to the problem of invasive plants?
OHVs have a huge potential for weed spread. Vehicles driving through populations of invasive plants often get seed mixed with dirt and mud on tire treads and undercarriages, move to another area and then drop seeds into a previously uninfested area. A study performed by Trunkle and Fay (1991) determined that an average of 1644 knapweed seeds became attached to a pickup truck after backing 40 feet through and infested area and then pulling back out. After driving one mile, 14% of the seeds were still attached, and after 10 miles, 8% remained attached. This type of seed attachment and dispersal is likely common for any number of weed species and shows the potential threat that motorized vehicle users can unknowingly bring to the landscape. In addition, continued OHV use in an area often reduces vegetation and exposes soil, creating favorable conditions for germination of weed seeds (Burke and Grime 1996, Hobbs and Heunneke 1992).
