Weeds Management > Other Tools

People have tired many of the following weed control practices with varying degrees of success. Most of these management techniques are applicable only to a limited number of plant species, are site specific and are usually not successful when used as your only means of weed control. If you are interested in utilizing any of these management tools control weeds contact the Missoula County Weed District to help develop the most cost-effective and sustainable weed management plan for your property.

Cultivation - Besides handpulling, cultivation is perhaps one of the oldest forms of weed control known to man. Depending on what you want to grow cultivation can be very labor intensive and costly. Since you are essentially plowing under all plants (weeds and desirables) and starting from scratch this method is recommended for only small-scale restoration projects in areas with extremely degraded native plant communities. The cost and labor required to grow only a single crop species following cultivation is much lower than if you decide to use this tool to restore an area to a natural state. Either way revegetation following cultivation should be done with a seed drill or by planting mature species rather than broadcast seeding.

Cultivation can be an effective way to control annuals, tap-rooted biennials, and perennial noxious weeds. Cultivation may have to be carried out a number of years to deplete the existing seed bank of noxious weeds. For example, cultivation together with annual (link to definition page) cropping for three years, followed by seeding to perennial cover can be an effective way of managing spotted knapweed. Due to remaining viable seeds in the soil, following up with some combination of hand pulling, herbicide, spot treatment, fertilizing, biological control, and proper grazing management is still required.

Fertilization - As a method by itself, fertilization will only cause noxious weeds to be more vigorous. However, studies with yellow starthistle have found fertilizing at the time of herbicide application or within the first two years after herbicide application has greatly increased the vigor of the beneficial vegetation and has made it more resistant to weed invasion.

Burning - Overall, fire has not been found effective in controlling noxious weeds. Small islands are left unburned and fires are very seldom hot enough to impact the root system or eliminate the viable seed in the soil. Fire may have a fit to remove standing and fallen litter and stimulate new growth, which enhances post-fire herbicide treatment.

Mulching - Applying a thick blanket of mulch is an effective way to discourage seedling growth. Over time, the organic matter adds plant nutrients and improves the water holding capacity of the soil. It is generally recommended that mulches be applied 3 to 4 inches deep to inhibit seed germination. However, to successfully control perennial weeds may need to be applied deeper. For range conditions, cost and practicality makes the use of mulches a less viable option but for smaller projects mulching has proven an effective tool for controlling regrowth of weeds.