HelpfulGardener.com

Yesterday I spotted this bug eating my tomatoes and potatoes. I sprayed the plants with soapy water. This morning the bugs are still eating those plants and even more plants have been totally consumed. I just sprayed with diluted tea tree oil, but I am so far not seeing any sign that they are dying or leaving. Anyone know what this bug is and/or what to do? If I don't stop them today my entire garden will be gone by tonight at the rate they are going.

Looks a little different from the ones I get but the fat abdomen and the shape Looks like BLISTER BEETLES.

Yes they are voracious. Don't touch with your hands -- they -- oh can't remember which end it comes from -- produce caustic liquid that can cause burn like rash and blisters on your skin. For immediate solution, wear kitchen gloves and use stick or other tool to knock them down into a cup or bucket (depending on extent of infestation) of soapy/sudsy water. They will drown and die in most satisfying way.

Look for juvies and eggs -- having said that I can't remember what they look like at the moment. Think I posted about them last year so I'll look for the link. Soapy water spray should be effective against the juvies but probably not strong enough for the adults.

Other members with experience using stronger remedies may have additional recommendations.

So sorry you are having to deal with that, sounds like a nasty one.

In my experience, soapy water spray works well for soft bodied insects like aphids, but isn't really effective for hard bodied ones like beetles (except when you can drown them in it, as applestar suggested)

What I would try would be diatomaceous earth.

Rodale Press recommended dusting everything with a 50-50 mixture of flour and garden lime. Dirtdoctor recommends kaolin clay:

https://www.dirtdoctor.com/Blister-Beetle_vq657.htm

Let us know what you try and how it works.

I can't tell, are the small dark things also bugs? They look like locusty type things but are not locusts. Use neem oil - that will prevent them from breeding for one. If you're looking for something to try immediately and not go to the shops then add powdered or crushed garlic to the spray. It might help prevent them eating the plants.

Edit to add: I didn't see the other reply but if that is right remove by hand then spray neem oil to prevent breeding of any you missed then try using diatomaceous earth around all your plants, which will kill anything moving over it.

Thanks. What's that bug confirmed. https://www.whatsthatbug.com/2013/06/12/ ... beetle-32/

I read this, grabbed some soap and a bucket, and headed out to start drowning bugs. It is so hot outside but we have made a dent in the population. Hopefully the plants without leaves can regrow them and not all will be lost. We will tackle the problem again this evening. Thanks again.

BTW, where is a good place to get Neem? I live in the boondocks--Wal-Mart is an hour away.

Neem hides in many places. The active chemical in neem is azadirachtin. I didn't even know I had neem in my possession until I found out the "azadirachtin" bit; I had a Greenlight brand "Rose Defense" spray whose active ingredient was azadirachtin. Dilute X amount of Rose Defense to Y amount of water, spray, etc.

It was neem! Duh....

I would recommend using neem towards the end of the day, when bees and other pollinators are less likely to be active. Neem acts on them, too, from what I've read, so on the "better safe than sorry" principle, as well as "only mad dogs and Englishmen go out in the noonday sun" principle, perhaps later in the day is best all around.

Cynthia H.
Sunset Zone 17, USDA Zone 9

Thanks for the info. Our plans have changed and suddenly we are able to make the hour drive to town. I will look for some Neem.

Speaking of heat, in the evening after milking the goat, I went to the garden and the bugs were basically gone. Only spotted a couple of them. Guessing they don't like the 98f temps either.

Now that I know what they are I can understand why the chickens ignored them. I went to a lot of work to catch some chickens to throw in the garden only to have them say, "no thank you, I will just hide in the corn if you don't mind".

When I went out this morning to check on the garden there were only a couple of bugs which got removed. Hopefully everything will grow some new leaves and survive.

Does anyone know what I can do in the future to prevent blister beetles from even coming to dine in the first place? Any companion plants ideas or other suggestions are appreciated.

UC Davis has a pdf on blister beetle management which says:

" There are no known predators or parasites that effectively control blister beetles."

But planting anything aromatic mixed in with your crop plants helps keep beetles of all sorts away. That would include basil, catnip, pennyroyal and other mints, nasturtium, marigold, rue, tansy.

I think there are different species of blister beetles, but here's an interesting factoid -- (a species of?) blister beetles is attracted to blooming alfalfa:

MANAGEMENT There are no known predators or parasites that effectively control blister beetles. Blister beetles are attracted to blooming alfalfa. Therefore, to reduce the incidence of blister beetles in alfalfa, cut hay before bloom. If beetles are found, remove the conditioner wheels from the swather in order to prevent crushing beetles. Also, these beetles are found on the edge of the field or congregated in groups within the field. Skip such areas when cutting or pick up the bales for these areas separately and isolate them from the rest of the field. No treatment thresholds have been established for blister beetles.

www.ipm.ucdavis.edu/PMG/r1301911.html

The one in the article photo doesn't match yours. The kind I get is called margined blister beetles, and they seemed to like beets and chard the best. At least they started with those, then moved onto my peppers.

I'm thinking if the species overwinters in the soil, then fall application of beneficial predatory nematodes may help. Perhaps neem will work. They are pretty easy to drown in soapy water, though. Oh, and their juvies were bright orange or red in my garden. I should start keeping watch for them since they came when it got really hot last summer, and we are getting into the July summer heat now. A big storm system is approaching from southwest today, and those seem to bring the hot weather pests along with the weather as well.

For immediate repellent, last year, I resorted to dropping them on the ground and stomping on them -- a variant of making bug smoothies in the blender and spraying the plants -- especially necessary in this case since the chemical they exude "cantharidin" can contaminate the crop. I can't say for sure that it helped though.

--ETA-- haha rainbowgardener got her post in with quote from same source while I was composing mine!

Oh look at this!
Which do you prefer? Blister Beetles or Grasshoppers?

Larval stages [of blister beetles] feed on grasshopper eggs or are predaceous and are thus considered to be beneficial, although a few species feed in nests of solitary bees.

https://insects.tamu.edu/fieldguide/bimg167.html

...In my area, we don't get the swarming kind of grasshopper pestilence -- I might see 2 or 3 of the big 3" ones at a time in my garden and they are often snatched up by the birds. Mostly the kind we get are the little ones that I only see grow to maybe 1" and the birds love them for their babies and there are plenty of other predators, too. At the moment, I'm not sure if they are different species of grasshoppers or if they are juvies and never get to grow up.

Interesting. it has been in the 100's lately and grasshoppers are plentiful right now.

Not sure if it is due to drowning so many beetles the other day or spraying the plants with the soapy water on Wed. and diluted tree tea oil on Thursday, but I can't find a single beetle today. Only spotted a couple yesterday but drove to town for a day of shopping so I only looked in the early morning.

I did look for Neem at Lowe's and even asked for help, but no one had any idea what product has it. So I still do not have Neem.