I’m a Vermont medical grower and a long time listener here since Ep. #11 and haven’t missed a DGC podcast yet. Keep ’em coming please…
Scottie’s Wake-n-Bake titled, “Wake & Bake America Root Aphids vs. Fungus Gnats”, was one the most useful and helpful videos in a long time. I too had been wondering why I could not control fungus gnats during our long cold Vermont winters, even while using BT as a preventative. As Growguru mentioned, I too had been confusing the sticky cards bugs as gnats, when in reality they were the dreaded root aphids.
Those RA’s has been giving me a hard time now for months…. very difficult to keep them under control.
But Growguru mentioned a root aphid prevention product that comes mixed with rice hulls which is added into soil/coco when transplanting. The product acts as a time release to keep those bad boys under control for quite a while.
This is something I really need to take for a test ride… what is the name of this product and how can I get some?
Dogbreath
If you are still in veg there are a few different things to go at it with. I would start with a liquid pyrethrum that will kill as many larvae and intermediates on contact as possible. I would have fresh cards or a bomb ready to get the fliers when they come out and set it off to kill anything out of the soil. Then you should get some met 52 (Metarhizium anisopliaestrain F52). This will take care of any remaining aphids. It will not kill any fungus gnats though so if you had a dual infestation they may stick around. Some people only use the met 52. Good luck with taking those out.
The professor has it spot on, you could also add grandevo and prf(pfr i cant remember) 97 if the met alone isnt cutting it
Thanks for the comments guys… but I have tried MET52 three times (heavy watering drench) as well as pyrethrum with no success…
…and many other attempts… spinosad, etc.
The prf 97 product….. did you perhaps mean Acephate 97UP?
I’ll give the grandevo a try…… starting to feel a little desperate….
BTW: It looks like MET52 has been discontinued…..
Dogbreath
No it is not Acephate 97 up it is called PRF 97 20% WDG here is a link to it http://www.forestrydistributing.com/en/pfr-97-20-wdg-microbial-insecticide-omri-listed-certis-usa
I’m gonna go ahead and chime in on this one. Being in Oregon we have to deal with very strict testing rules. I used to use all kinds of sprays and bombs and now just about any chemical treatment will lead to a failure in tests. I’ve recently started using biological controls and couldn’t be happier with the results.
Use Preadtory Mites. Stratiolaelaps scimitus is a native species of soil-dwelling mite, which feeds on small insects and mites (e.g. springtails, root mealybug crawlers, and spider mites). Adults are tan in color, less than 1 mm long (1/20th in.) and move rapidly over the soil surface. They live, eat, and reproduce in the soil medium and walkways on the greenhouse floor. Stratiolaelaps is most effective when applied before fungus gnat populations become established or when numbers are still low (below 10 per trap, per week).
Two applications of Stratiolaelaps per crop cycle are usually sufficient if used early in the season. The second application should be made 2-3 weeks after the first. Apply Stratiolaelaps shortly within the first few weeks of planting and before fungus gnat levels reach more than 20 adults per trap, per week. To control high numbers of fungus gnats, use of Stratiolaelaps can be integrated with insect parasitic nematodes, which control the larval stage of fungus gnats.
I’m using these along with Amblyseius andersoni (for spider mites and Russet mites), Persimilis (for Spider mites) and Amblyseius swirskii ( for broad mites, thrips, and white flies). I only have a small spider mite infestation right now but its better to hit them hard on some preventatives than to deal with a full blown infestation.
My 2 cents.
Oh and you can go over to http://www.naturalenemiesbiocontrol.com/ and fill out a new customer form and they will figure out a program for you that works best.