URGENT Question Does anyone have experience using beneficial nematodes for thrip control?

GthaEnigma

Canna-Arborist
Rogue swarm hit my girls a few days ago. Kangen ionized water is ineffective. I have applied first round of captn jacks(spinosad). I want to know if nematodes can effectively help wipe out or contain the horde in conjuction with the cap jacks or just a waste of money?
 

SmithsJunk

In Bloom
Rogue swarm hit my girls a few days ago. Kangen ionized water is ineffective. I have applied first round of captn jacks(spinosad). I want to know if nematodes can effectively help wipe out or contain the horde in conjuction with the cap jacks or just a waste of money?

Need to know exactly what kind of pests you're dealing with? Apparently you're trying to run organic? What stage are your girls in, veg or flower? If in flower, how far along and how close to harvest?

I found Spinosad to be ineffective against all but a few pests. Nematodes, just like predatory mites, are preventative measures highly unlikely to be able to bring an infestatoin under control. If you are dealing with fungus gnats apple cider vinegar and regular Dawn dish soap (not antibacterial) should do the trick for a soil drench.
 

GthaEnigma

Canna-Arborist
Outdoor plants. The pest is thrips. The level of infestation is light, spinosad application has got them on the run, just looking for the coup d grace. My thinking is the majority of are dead. They came from a field down the way where they were doing some heavy weed mowing. Trying to get any in the instar stage, if there are any, to keep a second wave from gaining a foothold.
 

SmithsJunk

In Bloom
Outdoor plants. The pest is thrips. The level of infestation is light, spinosad application has got them on the run, just looking for the coup d grace. My thinking is the majority of are dead. They came from a field down the way where they were doing some heavy weed mowing. Trying to get any in the instar stage, if there are any, to keep a second wave from gaining a foothold.

Thrips are generally fairly benign on outdoor plants. I usually just ignore them. The coup d grace would be pyrethrin. It's derived from chrysanthemums so it's organic and it has an extremely short half life in the the sunlight, I think 3 days but I suggest you verify that for yourself. I don't recommend using it after flowers begin to stack so it can't be trapped between swelling calyces and degrade more slowly. Pyrethrin is by far the most effective organic pesticide I know of and, to the best of my knowledge, is lethal to every pest (and beneficial bugs as well so use wisely and in the evening to avoid killing bees).
 

SmithsJunk

In Bloom
I have in the past ignored them, but the kangen has them looking so healthy at this stage i figured i'm bored , lets do battle.

Makes sense, though they do mostly cosmetic damage on the water leaves it is somewhat annoying when they ugly up my girls. You may want to be careful about how often you use a pesticide unnecessarily. There are other far more formidable pests like broad and russet mites that are extremely adaptive due to rapid successive generational turnovers and we don't want them to develope immunities.
 

spyralout

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Thrips are generally fairly benign on outdoor plants. I usually just ignore them. The coup d grace would be pyrethrin. It's derived from chrysanthemums so it's organic and it has an extremely short half life in the the sunlight, I think 3 days but I suggest you verify that for yourself. I don't recommend using it after flowers begin to stack so it can't be trapped between swelling calyces and degrade more slowly. Pyrethrin is by far the most effective organic pesticide I know of and, to the best of my knowledge, is lethal to every pest (and beneficial bugs as well so use wisely and in the evening to avoid killing bees).
Speaking from an inorganic view. Pyrethrin bombs have been very effective, even on spider mites, indoors. Just need several applications. I know bombs won't work outdoors but just giving perspective.
 

SmithsJunk

In Bloom
Speaking from an inorganic view. Pyrethrin bombs have been very effective, even on spider mites, indoors. Just need several applications. I know bombs won't work outdoors but just giving perspective.

Absolutely, I just fired off a Doktor Doom in the greenhouse last night to do a spider mite cleanse. Pyrethrin is my 2ndary line of defense, generally I use Triazicide up to the 2nd-3rd week of flower, depending on how quickly the flowers start to stack. Over the last few years broad mites have become a regular yearly pest. Triazicide need only be applied once to get a little over 30 days systemic protection and in my experience it has a 100% broad mite kill rate. I can afford to let spider mites get a little out of hand and they might tent a few nuggs, but the phytotoxins from just a slight infestation of broad mites can wipe out a whole crop in a couple-few weeks. The phytotoxins linger in the tissues even after all the mites are dead so even a moderately healthy looking plant can be under a death sentence once that systemic tipping point is reached. Pyrethrins take several applications and even with it's excellent effectiveness, 99.99999% isn't good enough when fighting broad mites.
 

SmithsJunk

In Bloom
Thankfully, i have only had russet mites once. They got my ace of spades plants a few years back. Nasty lil bastids. According to the literature the kangen kills all spider and russet mites. It is the only reason i am going after the thrips with spinosad. Otherwise i would let them be.

Broads and russets are very hard to eliminate for two reasons. The 1st is because they reach their reproductive stage in about a week giving them a huge advantage in genetic adaptations. The 2nd and IMO the most overlooked reason, their sise. There are plenty of things that can kill them on contact but because they're only about .2mm those treatments won't reach them all without a surfactant due to the combination of water's surface tension and the plant's trichome hairs. Even with surface tension broken it's nearly impossible to fully coat every cannabis surface making contact killing agents highly ineffective. This leaves the only truly effective control as systemic. They cannot escape a poisoned food supply.

We must be careful when combining surfactants and pesticides because the combination of the two can dramatically change the way the poisons interact with the plant tissue. What is normally a surface only pesticide with a half life of a few days may turn into a systemic that takes weeks to dissipate and the label/MSDS often won't address this unless it's made to do so or a common practice.

Maybe adding yucca to Kanga water can increase it's effectiveness, though I don't if this will effect it's charge. Something to research.
 

SmithsJunk

In Bloom
AzaMax OMRI listed for organic gardening

AzaMax is a great pesticide to keep spider mites under control, though it has several drawbacks. It doesn't completely eradicate spider mites, is ineffective against broads and russets, it's expensive, and will taint the flavor of the flowers if used late into bloom. On the positive side, it's absolutely safe to mammals, it has a 90%+ kill rate on 2Spot spider mites, and it can be used right up till harvest in dire situations.

I used Azamax the 1st year I grew, switched to Triazicide because of it's 100% kill rate on everything and it's only $10 or less per bottle. It is not organic, but people don't generally realise that just because a pesticide is derived from a natural source doesn't mean it's any safer. Triazicide is actually safer than pyrethrin if accidentally ingested and is only considered "mildly toxic" to mammals. I'm only more careful with it because it's a sytemic that lingers quite some time.

My infestation. 2Spot spider mites after the chop. 10's of thousands of them. As the day warmed up they congregated into these masses that looked to almost move like an orange liquid. This is the biggest infestation I've ever had. I misted them with hydrogen peroxide to thin out their numbers and it melted their webs into plastic looking sheets. They hit so late in the flower cycle there wasn't much that could be done about it. I kept most of the plants in tact to draw them out of the flowers and up onto the bases or into the popcorn. I turned off my fans and closed up the shed to cook them out. That made the majority of them leave the plants.
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