Reducing Risk in Invasive Species Management.

Military regular and reserve components may often train at several locations in a year, and may also conduct exercises on various public lands as well. The vehicles and equipment must be driven or transported from place to place. Only a few locations require vehicles to be systematically cleaned before entering. Forest managers, ranchers, research scientists and the general public also operate vehicles off-road. Whoever performs it, this movement of vehicles, persons and equipment has the potential to transport seeds and other plant parts among locations where vehicles have been stored or operated. Just how great IS this risk, and what steps may be taken to completely or partially alleviate the risk? Research efforts have allowed the risk associated with such activities to be quantified. One aspect determined how many seeds can be accrued and quantified the potential for civilian and military vehicles to pick up weed seeds when they are operated either on or off road, and also how much of the seed load is lost along the driving route between the field site and the destination. These studies have shown that considerable seed loads may be acquired, and that they remain largely intact over hundreds of kilometers on paved or unpaved roads in dry weather. The second focus was on the effectiveness of existing cleaning methodologies to remove soil, seeds and other propagules from the vehicles. It was found that cleaning using field-portable equipment typically removes up to 80+% of the soil on a vehicle. This clearly reduces risk of transport from place to place, but does not eliminate it. The data and risk assessments are applicable to all types of vehicles and all public and private operators of the vehicles, including the military, forest managers, private farmers and ranchers, and the recreational public.