From A.J., a “mom-and-pop” grower in Northern California, September 7, 2014
I saw that you wrote an article about a trimmer getting sick from Avid. Well I thought I’d write you because Avid is now this looming element in my life and I thought you might be interested in this. So Russet Mites and/or Broad Mites seem to be this years epidemic in my small town. They are micrcoscopic, easy to misdiagnose and can take out an entire garden. The can also spread from dried product to infest gardens. The most common product, it seems, that is used to defend against these pests is Avid. It’s available under the counter at garden stores and via Amazon. I have the pest and Avid was recommended to me but when I got it in the mail and read the instructions I had serious concerns about using it. I am going to continue to pursue other routes of action because it seems so toxic, to the applicant, the environment and obviously the end user. However, I’m terrified that if I don’t use it I’ll lose everything! Maybe this isn’t a new thing, but it’s new to me and this community. Also at the garden store the guy who I talked to about it seemed to agree that it was this year’s plague and most people are reaching for the highly toxic stuff.
We consulted the man who wrote the book on Cannabis pests, John McPartland. He advises:
Avid is nasty, I wouldn’t use it.
Russet mites and broad mites are both a bitch.
No commercially available biocontrol is effective, unless she can source Zetzellia mali, a predatory mite.
Spraying hort oil or sulphur sprays work against some russet mites, but not the hemp russet mite.
Hillig killed hemp russet mites by enclosing plants in large plastic bags and filling the bags with CO2 for two hours or more.
We asked A.J. what she knew about the destruction wrought by the hemp russet mite. She replied:
They stunt the plant, the leaves turn yellow and drop while the mites suck the resin out of the developing flowers. Amazing how destructive these invisible pests are. There are a few things the leaves will do to give you a sure ID and of course watching the flowers shrivel tells you what you you’re dealing with. Oh, and when you hear that your neighbors have it, it’s usually a good sign that you have it, too. It can easily be confused as a nutrient deficiency, rust, anything, because they are microscopic. It also spreads fast. I was told by my friend that I should either use Avid or kiss my garden good bye. Wow!
I’ve been doing lots of research on this and it turns out that in Canada and New Zealand Avid is used on commercial food crops and in some cases it’s used in the US ,too. It is regularly sold under the counter at garden centers, i read an interesting article written by someone in Berkeley about this. The family of the mite is the Eriophyoid and I found the most interesting information by googling that. These things spread easily, by wind, on clothes, etc., AND the eggs can overwinter. Who needs CAMP when you got russet mites?
On webforums addressing this, lots of the posts are from this year and last year. I also read that Colorado is dealing with this big time. That’s not surprising. One thing I’m thinking about are seasonal workers (who are mostly women) who deal with this stuff day after day after day, without properly protecting themselves from residues that they probably don’t even know are present. The warning label on Avid directly says that exposure could lead to birth defects! I’ve never asked an employer what they’ve sprayed on their plants, how long ago the application was applied and how I can protect myself from its effects. I’ve never thought about it before but it’s a serious concern.
