Extension Viewpoints

Species spotlight: Russian knapweed gall wasp


The naming conventions of biocontrol agents are pretty self-explanatory. 

In this case, the Russian knapweed gall wasp is a wasp that forms galls on Russian knapweed. 

Before we take a deep dive into this beneficial, we will quickly define what a biocontrol agent is: an insect or pathogen that controls a pest. Biocontrols are host-specific and only damage the target species.

Russian knapweed gall wasps are tiny, stingless wasps that are about the size of a pinhead. In the spring they emerge as adults from galls formed by their egg and larval form in the stem of Russian knapweed and reproduce before dispersing and laying eggs in the stem of new shoots of Russian knapweed plants. 

They are only active for about 10-15 days as adults before they die, and their progeny start the cycle over again. 

Galling the Russian knapweed plants weakens the root system by requiring more energy in the upward growth and the plants are more susceptible to disease. 

Many patches of Russian knapweed have been infected with rust fungus one season after a gall wasp release. Russian knapweed gall wasps are available from the Palisade Insectary, and locally we have several nursery sites in Archuleta County and can distribute the wasps in gall form. 

Colorado Cottage Foods certification

There will be a Colorado Cottage Foods certification class on June 5 from 12:30 to 5 p.m. Check out our Facebook page for more information.

CPR and first aid classes

CPR and first aid certification classes are offered every other month at the CSU Extension office, generally on the second Monday and Wednesday from 6 to 10 p.m. The cost for the classes is $80 for combined CPR/first aid and $55 for CPR, first aid or recertification. Call the Extension office at (970) 246-5931 to register. 

Check out the online option on our website, https://archuleta.extension.colostate.edu/.