Organic soil growers might find our latest blog interesting.
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Does this mean growers who use products like Great White could be in trouble? Great White from Plant Success has two species of trichoderma and 16 different species of mycorrhizae. There are several products on the market similar in composition. What could this mean for these products?
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Could is the operative word. Because the TYM test is a total count of all yeast, molds, and fungi, growers who use those products could be inflating their numbers. Having said that, how much is still unknown. As the article states:
“This underscores the notion that Total Yeast and Mold tests are poor indicators of safety. A low TYM result does not mean a cannabis sample is free of pathogens, and a high TYM result doesn’t necessarily mean a sample is harmful to consumers.”
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Any microbe that lives in or on the vegetative tissue and is cultural can cause failure. Mycorrhizal fungi stick to the roots so will not cause failures.
Beneficial microbes that will cause failures include yeast (products like nuke em), lactic acid bacteria like bacillus sp. , trichoderma, and most other culturable microbial products especially when used as a foliar, as well as many other benign organisms. A side note, you won’t fail for powdery mildew on these tests as it’s not culturable in this way. You would need to have an extremely large population of trichoderma to fail in most states, I’d be more concerned with yeast which can be extremely abundant especially surrounding persons of questionable hygiene. I have no data at the moment but I currently recommend cessation of microbial products within the first 2-3 weeks of flower, with the exception of soil borne microbes like mycorhizzae or Mammoth P. EM and knf solutions are especially risky as often the microbial populations aren’t characterised so there’s no way of predicting if you’re introducing endophytes or to what level. Hopefully I will get more data working with some of my organic clients soon.
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I saw some numbers out of the EU on last stage control of beneficials in glasshouse strawberry production. I think the recommendation was like a spray with a sodium chlorine at like 2 ppm of chlorine the day before harvest. It kills all the strawberries natural yeast that is added during production. The key in the article looked to be based on the half-life of free chlorine. They want unmeasurable chlorine at harvest and shipment.
When we where doing some work with drying cut flowers we played with flash freezing in liquid nitrogen and then into a homemade freeze dryer. Our total mold counts where low enough for export to the EU. Of the top of my head the total mold count for grain and Aspergillus is in the single digits ppm. Yeasts and Rotherham molds was in the 50 range.
We saw that naturally drying saw elevation in total mold, post harvest. We tried a flash pasteurization method but that just causes more cost than it was worth.
One of the big post harvest physiologist published work on mold and hemp cerca 1942. Mold was a big problem for the high quality rope production. I want to say the paper came out of either Cornell or Kentuky. We need a modern post harvest physiologist to do some definitive work on canabis curing.
I don’t know if the hop producers have a mold standard, but they must. It’s is the thing all the micro breweries bitch most about. Stray molds entering into there production cycle. Tiny amounts change the grading on hopps
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