Department Header For Noxious Weed Division
Yellowstone County, Montana
Noxious Weed
Weed Control Methods Contact Department

1. PREVENTION:  The practice of not allowing noxious weeds to become established.  Prevention is the most effective, economical and desired weed control practice.  Practices include the use of certified seed, the of weed seed free hay, the use of clean gravel, soil and fill dirt, maintaining fence rows, irrigation ditches and all non-crop areas weed free.  Always reseed areas that have been disturbed.

2. CULTURAL CONTROL: The integration of components to minimize the impact of weeds.  Selecting manageable fields, rotating crops, disrupting weed life cycles, planting competitive crops and altering planting dates.

3. MECHANICAL:  Using methods to physically remove target weeds.  Cultivation, hoeing, hand pulling, and mowing are commonly used.  The use of cultivation is usually limited to farm/crop land and must be persistently cultivated to control perennial weed species.

4. BIOLOGICAL:  Involves the introduction and establishment of selected natural enemies of a particular weed species.  This may include insects, fungi, and diseases that attack the target weed while not affecting desirable species.  Effective biocontrol depends on the use of several insects that attack different plant parts.  Effective biocontrol should increase as insects become more available.

Bug Collection at Pompeys Pillar
Bug Collection at Pompeys Pillar

Bug Collection at Pompey's Pillar

5. CHEMICAL CONTROL: The use of herbicides to control noxious weeds.  Chemical control is the most commonly used method of weed control.  If used properly and according to label directions, herbicides are a very effective means of control.  Although chemicals can be expensive, they are still one of the most economic methods of control once weeds become established.

6. INTEGRATED PEST MANAGEMENT: One control method itself seldom provides complete control.  Integrated pest management (IPM), is approaching weed control by combining two or more methods to improve results.  The Yellowstone County Weed District provides a sound IPM approach, with detailed involvement in all methods of weed control.