Predatory Mites - Again

[aclum]

Hi,

I realize this has been discussed to some degree before, but I still have some questions on predatory mites for russet mites and spider mites

I've had problems with russet mites for a while and have been unable to control them with limited spraying of wettable sulfur and Take Down Garden Spray (not at the same time!!). I really dislike spraying and nearly wound up in the hospital not too long ago after misusing (I think) the Take Down. But I have GOT to do something before I lose all of my plants and have been looking into using predatory mites.

Hydro-gardens offers number of species of predatory mites that would seem to be effective, but the shipping costs make them prohibitively expensive for me. There are other less expensive sources (due to free shipping) namely on Amazon, and I could probably find more if I did a more thorough web search. (I'll post a link to an example in an edit to this post - I'm afraid I'll lose what I've written if I try to do it midstream).

I'm wondering if the predatory mites will be effective in the hot, dry, central California summer weather. How soon can I "apply" predatory mites after spraying other things - like dilute bleach solution, sulfur, fungicides, etc? Will any subsequent spraying - or even blasts of plain water to dislodge aphids, etc. kill the predatory mites?

From VCScott's thread from last July (I think), did you all end up using predatory mites and, if so, how did they work out? What species of mite did you use?

Thanks for any advice!

Anne

[aclum]

Been doing a bit of research and it seems like this is what I would need for my climate in the Central Valley of CA:

http://www.buglogical.com/spider-mit...-occidentalis/

It's way more than I need but seems like I could keep them cool in a dedicated small refrigerator we have in the garage to put them into semi-hibernation as described and get a number of applications out of the order.

Unfortunately can't find any available with free shipping and have to ship overnight so they'd be pretty pricey (about $75 for me), but if they worked well all season, and I didn't have to spray, it would probably be worth it.

I suppose than if I go to biological (need to do more research), I can't go with various pesticides and would have to get biological for other pests, too....

What do you all (or anyone ) think?

ON EDIT: Found a much better price here:

http://www.evergreengrowers.com/gale...talis-280.html

$45 including overnight shipping
BTW, Hydro-Gardens seems to list this species as first choice for Russet Mites (as well as being effective on spider mites).


Anne

[rnewste]

Anne,

I tried 7000 Ladybugs over a 3 week period in April but the Whiteflies just seemed to just laugh at them. Within a few days all of the Ladybugs had flown off, and the Whiteflies remained entrenched - that is when I opted for the Spinosad and Botanigard. Wish the predatory insects would have worked - but as a last resort the sprays were my only option....

Raybo

EDIT: These two statements on the website seem in confliction:

They are able to hunt in extremely hot conditions, without requiring a high humidity (at least 50%).

Use in Biological Control: Occidentalis feeds primarily on spider mite nymphs and adults, but not eggs. It will also feed on pollen when mite populations are low. The predators are well adapted to hot conditions as long as relative humidity is over 50%.

[aclum]

Hi Raybo,

Thanks for responding! And for pointing out the humidity contradiction. Here's another version I've seen on several sites:

http://soundhorticulture.com/cms/wp-...Tech-Sheet.pdf

My conclusion is that the over 50% is wrong, and 30-60% being optimal is correct. (I do like that the ideal temp range goes up to 115 degrees!!). Right now my outdoor sensors suspended in with the tomatoes are just reading 1% RH but 30+% in the general backyard - so humidity could be a problem.

So far I haven't had any real whitefly problems and very few thrips. The sticky insect traps seem to be keeping those under control for the most part. I'm concentrating on the russet mites for the moment, but I think lacewings might work for the whiteflies and maybe thrips - and not fly away like ladybugs. The world of beneficial insects is a "whole nother thing" for me .

BTW, saw the botaniguard listed in the hydro-gardens catalog. Looks really interesting. Let us know how it works!

Anne

PS - Enjoyed your Dona photos on other threads. I've got two in the garden (one grafted one not) and so far they're both doing really well (the exception rather than the rule in my garden this year, alas). They certainly are dependable (knock on wood)!

[rnewste]

Anne,

Unrelated, but I was at the local nursery (Yamagamis in Cupertino) picking up some orchard bark for the EarthTainers and they still have racks of unsold plants. Picked up 2 Momotaro and 3 New Mex Joe Parker to stick in somewhere.

Raybo

[VC Scott]

Anne:

I used Take Down a couple times last year and it was effective in keeping the russet mites in check.

My strategy is far more directed toward prevention rather than treatment. First, other than tomatoes, all plants in the nightshade family are kept away from the tomato garden. This includes jimsom weed, which grows naturally in SoCal. Anything in the nightshade family can be a host to the russet mites.

Second, when seedlings go out a layer of straw is added both beneath the plants and in the middle of the rows. Wind can blow dust onto the plants and the dust carries the tiny mites. Keep down the dust and you can prevent an infestation.

Third, I try never to let a leaf touch the ground. You don't want to provide ladders for the mites to crawl up.

Fourth, I plant some wispy leaf varieties that act as sentinels. They always seem to be the first to fall to the russet mites.

Fifth, keep your plants healthy. Healthy plants seem to fight off everything better.

This year I have used a little wettable sulfer at the first sign of trouble. So far I only sprayed once and that was limited to just a few plants out of 65. I am not sure it was spider mites, but when you see the lower leafs start to curl, that is the first sign of trouble.

I hope RedBarron chimes in because he knows about predatory mites and I am trying to emulate his permaculture techniques to the extent I can in my garden.

[Cole_Robbie]

Get a magnifying glass so that you can watch your predator mites. They remind me of the velociraptors from Jurassic Park. Spider mites look like cows with a mosquito proboscis. The predator mites are much faster, and take bites out of the spider mites as they run by them. It seems like the spider mites have no defense at all - but their defense is their massive amounts of eggs that seem to hatch out in staggered fashion. The predator mites eat all the living spider mites, but die or wander off before the final round of eggs has hatched out.

Hot Shot No-Pest Strips will kill spider mites, but not everyone wants to be around a chemical pesticide.

[Redbaron]

Originally Posted by VC Scott

I hope RedBarron chimes in because he knows about predatory mites and I am trying to emulate his permaculture techniques to the extent I can in my garden.

I haven't had to add any more predatory mites. I have a stable population of them. Of course now that I said that, this will be the year my theories fail! hahahahaha

It seems to me that the way to keep the predators is to have biodiversity. When the russet mites are not eating your tomatoes, what's a predatory mite going to eat? They starve, a bit of dust blows in with spider or russet mites, and with all your predators starved and gone, they have at it.

So I try to always have all sorts of "weeds" all over between rows, and companion plants in rows, so that there is always a few pests in the weeds and the pests are live critters for the predators to eat. They never leave, and when a russet does blow in with the wind, he drops right into the arms of our friendly predator population. Muahahahahaha

I realise that is the opposite of the standard advise. I am not going to advise someone to do the opposite of what experts say. I am not an expert. I generally do the opposite of the experts in all my gardening. Mostly it works, but I still can't grow an eggplant grrrrrrrrr Yet I still keep trying every year! Got my first ever eggplant last year. But what expert has tree frogs living in their garden? Does anyone know how many bugs a tree frog eats? I don't, but it has got to be a lot!

BTW if you ever get lucky enough to spot a predatory mite at work it is REALLY cool to watch. They are tiny though. Really really tiny. But they are like miniature tasmanian devils! If I had one of those after me I'd find some other plant to eat. Scares me!

[Tracydr]

Check Arbico. They have all sorts of predator insects and prices don't seem to high for most. I've not tried the predator mites but I'm very curious to see if they work. Other than sulfur, the only thing that's really worked for me is Adams Flea and tick spray with IGR. I know it's not organize but sometimes you get desperate when everything is dying.
I'm currently trying azamax mixed with Neem. I just used it for the first time so we'll see. I'm catching them earlier than I have in the past, except for my Sungold and Matt's Wild Cherry.

[Tracydr]

Will the Hot Shot pest strip kill beneficial insects? Does it kill ants? Trying to control the ants and aphids in my cowpeas.
If they don't hurt beneficials I will buy some and put them around the worst of my tomatoes with spider mites.
Oh, also do they kill Black Widows? I have a spider problem starting on my back porch, even though my husband has been prowling around with the flashlight and killing them.

[Tracydr]

Originally Posted by Redbaron

I haven't had to add any more predatory mites. I have a stable population of them. Of course now that I said that, this will be the year my theories fail! hahahahaha

It seems to me that the way to keep the predators is to have biodiversity. When the russet mites are not eating your tomatoes, what's a predatory mite going to eat? They starve, a bit of dust blows in with spider or russet mites, and with all your predators starved and gone, they have at it.

So I try to always have all sorts of "weeds" all over between rows, and companion plants in rows, so that there is always a few pests in the weeds and the pests are live critters for the predators to eat. They never leave, and when a russet does blow in with the wind, he drops right into the arms of our friendly predator population. Muahahahahaha

I realise that is the opposite of the standard advise. I am not going to advise someone to do the opposite of what experts say. I am not an expert. I generally do the opposite of the experts in all my gardening. Mostly it works, but I still can't grow an eggplant grrrrrrrrr Yet I still keep trying every year! Got my first ever eggplant last year. But what expert has tree frogs living in their garden? Does anyone know how many bugs a tree frog eats? I don't, but it has got to be a lot!

BTW if you ever get lucky enough to spot a predatory mite at work it is REALLY cool to watch. They are tiny though. Really really tiny. But they are like miniature tasmanian devils! If I had one of those after me I'd find some other plant to eat. Scares me!

If you want some trap plants sunflowers and marigolds seem to be best for attracting spider mites.

[aclum]

Hi,

Thanks everyone for all the responses and follow-up discussions!

I went ahead and ordered 1000 of the galendromus occidentalis from Evergreen Growers Supply today. I was 28 minutes past the ordering deadline for next week delivery so, unless they make an exception, I probably won't get them until the week after next. Cost was just about $45 INCLUDING shipping. Most other sources (including Arbico) were about $45 without shipping. I did like the Arbico description of the mite, though . (Particularly regarding the humidity range). I think the humidity gauges in the tomato beds are defunct (they always read 1%!!), but weather underground generally has our humidity in the 20-30% range so think I'll be OK with the mites

I appreciate all the suggestions. Unfortunately, I can't do the straw on my paths and am stuck with dirt, but the beds themselves are covered in silver plastic mulch. No real trap plants or weeds around, but dwarf fruit trees and lawn on either side of the garden that might provide some distraction for the russet mites.
I love the idea of sunflowers and will try to squeeze some of those into or near the main veggie garden. Other than the mite afflicted parts of the plants, they're pretty healthy looking, but I'll give them a little TTF this weekend to help them out a bit. New growth is good and I have a decent amount of flowering and green fruit (although nowhere near as nice as last year).

BTW, there used to be an old joke that: She's so (whatever), she wears no-pest strips for earrings !! Even though I'm not really into the pesticide thing, I'd use them if they killed black widow spiders ! I'm mainly opposed to using sprays due to respiratory problems and having to work from a wheelchair that limits my ability to stay out of harm's way when spraying stuff.

As far as the predator mites having food after eating all the russet and spider mites, the info I've read says that the predator mites can eat pollen and I'm guessing they might have a continuing (but hopefully somewhat limited) supply of prey mites kicked up from the dirt and dust on the paths between the beds so they shouldn't starve.

Although I've been pretty sure that I have russet mites, I only actually REALLY saw them through my loupe very recently. I finally used a high enough power and, more importantly, held the lens over the plant long enough to actually see the mites MOVE. ! GROSS! BTW, there's a youtube video, that I haven't looked at that apparently shows a predator mite going after a prey mite. Will check it out one of these days.

Heard from Evergreen Growers Supply in response to an earlier inquiry and apparently the predator mites can go into the garden 48 hours after Take Down or a few days after a Sulfur spray. So, until my mites arrive, I MIGHT use a bit of these here and there or might just try a bit of soapy water.

Someone mentioned the first signs of the mites. What I've noticed first is a greasy appearance to the underside of the leaves, then curling, bronzing, to browning, and finally crispy leaves that fall off.

So... My current plan is to get the mites, mix them with extra corn grits, apply some to the garden, refrigerate the rest at an appropriate temp and hopefully have some still viable to apply again in another week or two. I'll let people know how it goes!

To Raybo.

From my years living in the Willow Glen area of San Jose, Yamagami's was always my favorite nursery and "worth a detour." (I got Carolyn's book there long ago ). I noticed that Momotaro was missing from your garden diagram and glad you were able to get one this late in the season from Yamagami's. They are amazing .

Anne

[Redbaron]

Originally Posted by Tracydr

If you want some trap plants sunflowers and marigolds seem to be best for attracting spider mites.

I grow them every year

[Ms. Jitomate]

"If you want some trap plants sunflowers and marigolds seem to be best for attracting spider mites."

This is true! I currently have healthy tomato plants but very unhealthy marigolds with spider mites. I have be spraying the tomato plants in the morning with water almost everyday to prevent mites. My marigolds are all around the tomato plants. I have not sprayed the marigolds because I don't want to splash water/dirt onto my tomatoes.

Should I be treating the marigolds to prevent them from going to the tomatoes? Marigolds are 5 to 7 inches away from the tomatoes.