Free Cannabis Pest/Hemp Russet Mite ID and Control Workshop This Saturday August 25th.

Join professional entomologist Katie Garrison for a free workshop on how to identify common cannabis pests, with specific emphasis on the dreaded hemp russet mite (HRM). Katie has spent several years working in acarology, the study of mites and ticks.

WHEN: Saturday August 25th 10-12 a.m.
Where: Plant Humboldt Cannabis Nursery, 6070 Briceland-Thorn Road, Redway CA 95560.
Who: Everyone welcome! Commercial cultivators, home growers, scientists, regulators, media, snake oil sellers (if you’re a pesticide manufacturer, we’d like you to make a donation to our costs).
Cost: Free, though we’ll have a tip jar.
Bring: Leaf samples (healthy or sickly—we’ll examine them all!)
More info: Call the nursery 707-923-5063 for more info. Leave a message and we’ll call you back. We’re officially closed for the season, so we don’t sit around by the phone. You can also email us at info at

Katie ( @cannabis_pest_p.i. on Instagram) is currently doing preliminary research for a formal HRM scientific study next season. She’s intentionally cultivating russet mites on her cannabis plants so she can teach you how to keep them off your plants. This is real science, not “I read it on the internet” or “the pesticide sales rep told me so”.

Do you have infested plants? Are you wondering what is causing those leaves to look sickly? Do your plants look great and you’re “absolutely sure” they don’t have HRM? Bring some leaf samples and we’ll look at them under the microscope. We’ll have anonymous sample bags available that you can drop your leaves into when you arrive, since some people might be a little shy about having everyone know what their plants are infested with.

* There will be two powerful microscopes with video monitors set up so you can get a clear view of cannabis pests and their identification.
* We’ll show you how to use inexpensive pocket microscopes available at most garden stores to ID pests.
* We’ll discuss permitted/organic IPM pest control measures you can take to protect your crop without resorting to banned pesticides or overpriced “snake oil” solutions.
* Myth busting! Most of what you’ve heard or read on hemp russet mites is likely BS. Bring your best rumors and leave with the facts as best as we know them (which is very little).

Plant Humboldt Cannabis Nursery is sponsoring this as a service to the cannabis community. In the absence of actual data, the thirst for knowledge has been filled with rumors, paranoia and snake oil sellers. We want to dispel rumors and help people learn common sense and cost-effective ways to deal with cannabis pests, particularly russet mites.

QUIZ: Test your knowledge of hemp russet mite rumors!
  1)  True/False? Hemp russet mites were sprayed by Cal Trans.
  2)  T/F? Hemp russet mites infest the lower branches, but the effects show up at the top of the plant.
  3)  T/F? Russet mites are a DEA conspiracy sprayed in chemtrails so Monsanto can take over the weed industry.
  4)  T/F? Russet mites are born pregnant.
  5)  T/F? Hemp russet mites are blown on the wind.
  6)  T/F? HRM are spread by insects or birds or animals or grower’s shoes/clothing.
  7)  T/F? If you have HRM, you can never grow in that spot again.
  8)  T/F? If your plants have HRM, the only way to get rid of them is to burn the plants and sterilize the area.
  9)  T/F? You can see HRM with the naked eye.
10)  T/F? You can diagnose hemp russet mites by looking at the leaves.
11)   Bonus question: T/F You are an expert. Or, your friend is an expert. Or the sales rep with the fancy bottle of snake oil is an expert.


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