Colorado Potato Beetles

[Teacher_Mike]

CPBs are regular diners in my garden. I hand pick when I can, crush eggs as often as possible, (thank goodness they are SO VERY orange when almost nothing else is in the patch...) and generally accept that they are going to be there. I try to avoid chemicals, but if CPBs come early and hard, it can get dicey for lagging plants.

Reading a thread in the eggplant forum about using summer turnips as traps for flea beetles, and it occured to me that perhaps I could plant a row of potatoes for the same purpose. I wouldn't much care if I didn't get much of a crop (although a few new potatoes with the first peas of the season is heaven in a bowl..)...but would this work in the intended way, or attract MORE CPBs, or just be adding a second course to their meal?

My biggest pests on my toms are the CPBs and stinkbugs later in the season...just in case anyone has any thoughts about THOSE critters, too.

[MsCowpea]

This is an excellent article on CPB--covers everything you can think of to control them organically.



http://www.attra.ncat.org/attra-pub/PDF/copotbeetl.pdf

[carolyn137]

I read it and found that it is really directed towards commercial famers who are organically certified.

For the home gardener I find that picking them off is fine as long as there aren't too many.

Then use BT Sand Diego or the tenebris one on the larvae and mop up with 5% Rotenone for the adults. It must be 5% b'c the standard 2% does not work.

That works well for me.

In my experience they go for eggplant first, then potatoes, then tomatoes, but when I've planted those close to the tomatoes it has not worked as an effective trap crop.

I can't see using the physical barriers they suggest for home gardening.

Some folks have had good succes with the Pyola that's mentioned, but I've not used it.

[Teacher_Mike]

Thanks for the link, MsCowpea - at first glance, it appears to offer some possible options that I have not heard about before.

Carolyn - clarify, please...

In my experience they go for eggplant first, then potatoes, then tomatoes, but when I've planted those close to the tomatoes it has not worked as an effective trap crop.

Does that mean that although they seem to prefer these plants in this order, none is strong enough to deter them from the tomatoes? Are you saying, then, that a row of potatoes would likely have no noticeable value (except for my aforementioned bowl of new peas and potatoes?)

[MsCowpea]

Carolyn, I usually find commericial brochures written for the certified organic gardener very helpful as the products are available to the homeowner as opposed to brochures written for the regular farmer where most chemicals (not all) are restricted use. Plus they think outside the box.

Teacher Mike--in case you don't wade through the whole thing these are some of the things mentioned a home gardener could try.

-mulching with wheat or rye straw (boy that's easy)
-borders of plants that attract natural enemies
-rotenone/pyrethrin combo. (last, last resort-used by less than 10% of certified organic farmers)
-neem
-pyola
-san diego bt (larval stage only)
-certain herbs that repel (no supporting research though)
-the vacuum thing could be accomplished as carolyn mentioned by simply picking them off

--the one thing I find the most interesting is Mycotrol (beauveria bassiana) -I have researched this in the past and desperately wanted to try it (for thrips), but could only find it in a large containers for a great deal of money. Hoping they will package it in smaller quantities. Big plus-It replicates in the environment.

-finally beneficial nematodes

((I found the trench business fascinating--did not realize they they could be trapped like that. They don't really explain the flaming technique very well--I saw it demonstrated during an Organic Gardening class offered by the U of Fl. and will get one of those flame throwers for an anniversary present or something. ))

[MsCowpea]

-forgot to say that I have tried Bull's Eye (for thrips) and found it to be effective

http://www.gardensalive.com/product.asp?pn=8756

They say it works against CPB.

[carolyn137]

(Does that mean that although they seem to prefer these plants in this order, none is strong enough to deter them from the tomatoes? Are you saying, then, that a row of potatoes would likely have no noticeable value (except for my aforementioned bowl of new peas and potatoes?)

Yes, that's exactly what I'm saying.

I may see a higher rate in CPB infestation on the eggplant and potatoes, but that doesn't stop the CPB's from transferring to the tomatoes.

And once on the tomatoes you know how easy it is to miss the orange egg clusters under the leaves and before you know it the munching larvae are on their way.

The adults really don't do that much damage except to mate right in front of you, , which then perpetuates the cycle.

But that's my experience over a many year period of time and I don't know if yours will be the same.

[Teacher_Mike]

I see.

(CRAP )

Well, I suppose if they're coming to dinner, there's no need to offer them seconds by planting potatoes, especially when I can have my heavenly bowl of new peas and potatoes with a quick stop at my local farm stand.

I must admit...smashing and smearing the orange eggs gives me a certain degree of pleasure that I never would have thought possible B.T. (before tomatoes.)

[tjg911]

that's odd, i never have cpb on my tomatoes but potatoes seem to draw every cpb between here and colorado! even the tomato plant that was touching the end of the potato row was not effected by cpb. my eggplants were 100-120' away on the driveway in containers. not a cpb went to them but that was out of the garden. when i don't grow potatoes i don't see cbp.

an effective organic pesticide for cpb is a bt that is SPECIFICLY for cpb NOT the one used for caterpillars. any decent gardening store should carry it, just be certain it is for cpb. i use the liquid concentrate and spray it. it only kills the larvae not the addults. it washes off in the rain and breaks down in the sun. it is best sprayed in the early morning or at least so the leaves can dry before dark. also due to dew at night i prefer to get it on early so the larvae can eat it before the dew could dilute it.

last summer i had excellent luck hand crushing the adults and larvae on potatoes. i did not spray once! i had 36' of potatoes with lots of foliage but the timing and throughness really paid off. it is very time consuming because you have to be very careful, those larvae are very small initially. the adults always drop so keep 1 hand abot 3" below them and you'll kil 3X as many. but if you kill all the adults for a few days and the larvae too you really disrupt their breeding. i only did this 3 times but it look an hour+ each time.


tom

[Worth1]

We have come a long way from using lead arsenate and I’m glad of it.