Appendix A: Troubleshooting Guide; When things go Wrong

From Bugwoodwiki

Wilson, L.M. and Randall, C.B. 2005. Biology and Biological Control of Knapweed. USDA Forest Service FHTET-2001-07. 3rd Edition. 110 p.

This guide is intended to assist those who encounter problems when establishing a biological control program. It identifies the probable cause of a typical problem and offers solutions.

Problem Probable Cause Solution
Bioagents unhealthy Physical damage to agents Prevent containers from colliding; use crush-proof containers.
Drowning Do not put water in containers. Prevent acumulation of excess moisture in the collection containers.
Excess or prolonged heat or cold Keep containers cool at all times; use coolers and blue ice packs; avoid exposure to direct sunlight while in transit.
Starvation Put knapweed foliage (no flowers, seeds, or roots) in containers.
Redistribution time Transport or ship agents immediately after collection.

Release agents at new site immediately upon arrival or receipt of agent.

Parasitism and/or disease Check source agents. Ensure the insect population is disease-free when collecting or receiving shipment.
Number of eggs low Agents past reproductive stage Collect at times of peak activity (i.e., insects are mating).
Sex ratio: not enough males or females Observe mating among bioagents before collecting; males often emerge earlier than females.
Synchrony Agents not synchronized with the knapweed growth stage; bioagnets require knapweed to be at specific growth stage for optimal oviposition.
Few bioagents collected Wrong method used Refer to Tables 11 and 12 for recommended collection time and technique.
Collection done at wrong time Refer to Tables 11 and 12 for recommended collection time and technique.
Collection technique Bioagents can be killed during sweeping or aspirating.

Use vacuum aspirator if aspirating by mouth is not working. Practice sweeping.

Conditions at time of collection wrong Refer to "Collecting Biocontrol Agents" and "Monitoring Biocontrol Agents" for guidelines on desirable weather conditions.
Agents not found after release Site is unsuitable Refer to "Collecting Biocontrol Agents."
Site too small Select a larger site with a dense, uniform stand of knapweed.
Pesticide used in area Select pesticide-free site.
Cannot locate release site Permanent location marker not obvious Use bright-colored wooden, metal, or plastic stake.
Map poorly or incorrectly drawn Check map; redraw with more detail or add landmarks.