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Thrips battle pt2 - predatory mite experiment! :)

Well - since my thrip vac didn't work too well, in fact didn't work at all, and I don't like the idea of spraying plants, I have another trick up my sleeve. 
 
Meet my mite army! 
 
mitesvthrips.png

 
(I did take both those pics with my macro lens...sadly no fight image yet!)
 
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The sachets are "amblyline CRS" and contain bran with a feed (a smaller harmless mite) along with eggs and hatchlings of the mite army - specifically amblyseius cucumeris. Officially the sachets are supposed to "dispense" 400 mites a week for around 6 weeks. That's an emergence rate of 2.4 per hour, ish. I can see it's higher than that though, right now.
They cost me £17 GBP for 8 sachets, so while not cheap, not that expensive either, and very low effort rate too - just hang them on the plants and wait for the mites.
 
Seller I bought them off here in the UK advises one per plant - but I'm doing about 1 per 4 plants as my plants are small and they look like a plague of mites! It's quite unnerving watching them pour out of the hole in the tops of the white bags like some horror film. I am sure I'll wake up covered in them one of these days! All this inside the house. Best not to think about it :)
 
By the time they arrived the thrips had pretty much taken over - I had something like 50 thrips on some plants, one plant had a LOT more so had to be disposed off, it was dropping leaves. 
 
Anyway - It's already 48 hours since I hung the sachets and it panned out like this:
 
12 hours in: a lot of mites dead and dying upside down on the aluminium foil mulches (this is an anti thrip measure btw!) - I think the mites are falling off the leaves. Bit of research later, turned off the fan and sprayed a bit of water from a fine mister, apparently this helps them hang on
 
24 hours in: no more mites seem to be falling off. Mites are everywhere but thrips are too
 
48 hours in - now: where have the thrips gone? I've checked every plant and not one in sight! Perhaps they're hiding. Or...perhaps they've been eaten. Time will tell. Still lots of mites on every plant - they are very active! 
 
I have to say this is surprisingly promising - to go from thrips everywhere, to zero thrips or nymph thrips after just 48 hours...! 
 
TBC :)
 
I've had tremendous success using predatory mites against my enemy, the broad mite. In fact, the use of predatory mites has been the single most successful means of control I have found (and prior to that, I tried a lot... including the use of full-blown chemical miticides... yes, I got that desperate and didn't know better at the time). It's good to hear that somebody else may have found their silver bullet against their enemy. :)
 
Keep us updated!
 
great info! how long do the mites stick around once their food source is exhausted? they dont start eating the plants do they?
 
gasificada said:
I've had tremendous success using predatory mites against my enemy, the broad mite. In fact, the use of predatory mites has been the single most successful means of control I have found (and prior to that, I tried a lot... including the use of full-blown chemical miticides... yes, I got that desperate and didn't know better at the time). It's good to hear that somebody else may have found their silver bullet against their enemy. :)
 
Keep us updated!
 
 
Cheers! I wish I'd known about these (or dared to use them) against broad mite last year! :)
 
 
 
gourdmaster said:
great info! how long do the mites stick around once their food source is exhausted? they dont start eating the plants do they?
 
Thanks! Well, apparently if you keep the sachets out of the sun (it dries them out) you get 6 weeks of new mites, but also apparently cucumeris can survive at least some time on pollen alone. So potentially - a lot longer than the life cycle of the thrips! And no, they don't eat plants, just pollen, broad mites, thrips, possibly also the larvae of other pests...
 
One major worry I have is of them leaving the pots - I don't like the idea of them hanging around the house in random places. So far, no sign of that. 
 
moosery said:
One major worry I have is of them leaving the pots - I don't like the idea of them hanging around the house in random places. So far, no sign of that. 
 
I dunno... I figure wherever they are hanging around, they are hanging around for a reason. ;)
 
The mites I use (neoseiulus californicus) are supposed to survive on pollen as an alternate food source too but they always seem to disappear when they have all but exhausted the broad mite feast (leaving the door open for reinfestation). :( Ah, but I figure they are moving in on the neighbour's broad mite populations and thus creating a broad mite free barrier around my yard. That's what I tell myself anyway. ;) Indeed it does seem like the broad mite numbers are getting fewer and fewer every year, though. Now, just as long as I don't end up eating those words any time in the near future...... haha.
 
Glad that worked! Now it would have been even more interesting if you managed to get a pic of a mite gorging on a thrips while the feast still lasted...
 
plaisir8 said:
Glad that worked! Now it would have been even more interesting if you managed to get a pic of a mite gorging on a thrips while the feast still lasted...
 
 
I tried..I honestly did! 
 
I thought these predators only eat the early nymph stage of thrips, but don't affect adults.  It's interesting that you found they seem to have rid your plants of all thrips in a 48 hour period.
 
SichuaneseFoodFan said:
I thought these predators only eat the early nymph stage of thrips, but don't affect adults.  It's interesting that you found they seem to have rid your plants of all thrips in a 48 hour period.
 
Yes, I read that. I'm not sure - except perhaps they withdrew when they saw a mite army approaching and flew off? It's not unlikely since they hide when a "squashy finger" approaches. If I saw a load of giant spiders approaching me I'd surely do the same! 
 
Update!
 
I have found some adults, all clustered together on one or two leaves on one plant, they do look like theyre hiding. also numbers like 8 at most, not tonnes like before.
I watched closely for a while, the mites didn't eat any of them but they're not afraid of them. Typically a mite would randomly walk up to an adult thrips*, and touch it, the thrips would dart away a few millimetres, and that's that. The mites don't walk straight. Crazy ziggy zaggy lines. The thrips walk in straight lines. 
 
Best guess is the mites are annoying the adult thrips and that's a good thing. It might mean that they thrip off! It lends some credence to my hiding thrip theory. 
 
It's all fascinating anyway. 
 
And - still zero baby thrips. So I'm still happy.
 
Hello! 
 
Yeah its some time since I treated. Here's my findings:
 
- It works. 
 
- Depending on the climate (humidity mainly) will depend how long the mites will hang around. They will die if its too dry, then you will have to buy more. This is not the end of the world. I had to repeat after about three weeks indoors. In the greenhouse where the humidity is higher, this wasnt necessary.
 
- The mites DO eat pollen to stay alive. I dissected many flowers as they fell off after pollination and there were nearly always mites hanging out inside.
 
- They really dont leave the plants, I would thoroughly recommend them indoors in residential as I had zero problems there
 
All that time has passed and my yields are great and the leaves are healthy without the puckering and silvering. I still see literally one or two thrips a week that seem to somehow evade the mites but I know that even if those lay eggs, the mites will eat them as soon as they hatch thus keeping the population to a very very small minority. I also know that I'm protected from broad mites!
 
One problem I did have is when I made the second order, the company sent me dead sachets. If you dont have a LOT of mites walking all over the sachets when they arrive, demand more, because those sachets are dead. The mites are visible to the naked eye, spider mite kinda size I guess. If I hadn't known this from my first sachets, it would have appeared not to work, when the problem was in fact faulty goods. Buy from a reputable supplier, and if you cant see mites, you dont got mites :)
 
In conclusion? Do it. These things work like magic, they really do. 
 
OK it's september and another update. I found a single thrip when harvesting a habanero. Annoyed squash later, and I spotted about five mites too. Seriously, I haven't treated since what, June? So they've managed to hang around keeping the thrip population down for all this time? I'm impressed. 
Oh, I'm not seeing ANY thrip damage of note, I had a good harvest in the end, tonnes of bhuts! 
 
Although the efficacy of predatory mites have been established...I was thinking about alternatives.
For example, does anybody know how thrips (or other small arthropod pest ie spider mites) interact with an increase of atmospheric anions?
 
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