Biological weed management utilizes insects to aid in the control of select noxious weed infestations. When used in an Integrated Weed Management Program, these insects are very effective. Effects may not be seen as quickly as compared to other methods, but their long-term influence has proven to be highly beneficial in the fight against noxious weeds.

 

There are different approaches to biological weed management. The "active" approach involves physically releasing insects, like the musk thistle seedhead weevil (left) or flea beetles, on select weed populations. The Adams County Weed Department has several sites where insects have been released and their progress carefully monitored.

 

The "passive" approach takes advantage of the migratory patterns of beneficial insects. An example that is common in Adams County is the work of the Painted Lady butterfly.

The Adams County Weed Department has used sheep to assist in the control of leafy spurge. Nic, the llama was kept with the sheep to protect them from predators. The grazing location was on a property along the South Platte River. The sheep grazed the spurge in the spring, flea beetles emerged during the summer, and a selective herbicide was applied in the fall. This is an example of an Integrated Weed Management (IWM) Program. More than one method is utilized to contain/eradicate large noxious weed infestations.

 

When dealing with large infestations, there is no "silver bullet", meaning don't rely on just one method. Whether it be grazing, insects, or herbicide treatments, you'll observe more effective results for the long-term when you use all of the tools in the "toolbox".

 

Kelly Uhing, Colorado Department of Agriculture

Disclaimer | EEO | Answerlink | Webmaster

Last updated 02-20-07