Pump Septic Tanks Now / Weed Seeds Dispersed by Vehicles

County Agent News

Dan Folske

October 31, 2011

Pump Septic Tanks Now

Accumulations of sludge and other material can cause problems in septic systems during the winter, so now is the time to get your septic tank cleaned and pumped. If you aren't sure whether the tank needs cleaning, you can use a pole with white toweling wrapped around one end to measure the depth of the sludge in the tank. The tank should be pumped when the sludge build up is 25% to 33% of the liquid capacity.

Septic System and Drainfield Basics

            If you are considering a new house in the country or need to replace an existing system The NDSU Extension Service publication AE-892 Individual Home Sewage Treatment Systems is a great bulletin which can help you understand and evaluate your sewage system options.

Weed Seeds Dispersed By Vehicles

With all the oilfield traffic, both locally and originating out of state, weed seeds hitching rides on vehicles is a big concern of county weed boards and ag producers in the state. The following article from Montana University News by Kimberley Taylor, Jane Mangoldvand & Lisa J. Rew explains that concern.

Field studies showed vehicles pick up and disperse seeds. ATVs picked up and carried more seeds off-trail than on-trail, with higher numbers in the fall than spring. Other vehicle types picked up more seeds when driven on wet than dry unpaved roads. Seeds fell off vehicles more rapidly under wet conditions, while few seeds fell off under dry conditions. Invasive weed species can be problematic and costly to control. It is more cost effective to prevent new invasions and eradicate small patches, than to spend money trying to control or eradicate large existing patches. Therefore, it is necessary to understand how weeds spread in order to prevent new invasions. The abundance of weeds along many roads suggests that vehicles may be acting as dispersal vectors. In fact, studies have found that passenger vehicles can carry anywhere from three to 135 seeds per vehicle. Vehicles have managed to spread over 500 different plant species. Vehicles are most likely picking up seeds from the road or roadside and then spreading them farther along the road. If vehicles transport seeds long distances, they may carry weed seed to areas where they do not yet occur. Once growing along roadsides, other types of dispersal may move the weeds farther into the surrounding area. The pervasiveness of roads means that vehicles could be a major mode of plant dispersal. In fact, a study done in Chile showed that an increase of roads in an area led to an increase in weed species. There are 4 million miles of roads in the U.S. that are split almost evenly between paved and unpaved surfaces. Eighty percent of the roads are rural and occur in all types of environments, reaching relatively remote and weed-free areas. Outdoor recreationists who travel on remote roads to trailheads or who ride ATVs off roads or designated trails may be unknowingly spreading weeds with their vehicles. Work at Montana State University measured the number of seeds picked up by vehicles and the distance seeds traveled on vehicles before they fell off. Different types of vehicles (trucks, ATVs, tracked vehicles), road surfaces (paved, unpaved, trails, off trails) and moisture conditions (wet and dry) were studied to determine how they affected seed dispersal. Understanding how many and how far seeds are transported by vehicles under different conditions will help direct prevention activities (wash stations, road closures, education, etc.) to reduce weed seed dispersal along trails and roads.