Cure For Cochineal?

[Tom]

Personally....... Use whatever pesticide that doesn't kill bees and will do the job and meanwhile buy their cactus from the store until the bugs are GONE and the poison is degraded and gone. I don't really see any of these half measures getting rid of these miserable little pests.

There's the problem. How do I know when the pesticide is degraded and gone? When is it safe to feed the pads from my 40 stands of cactus? What do I do with the 100's of pounds of pads that are produced while the pesticide is still active and toxic? So many questions…

Are there pesticides, that will kill these things, but not kill bees? I'm not too worried about the bees because the bees have no reason to hang around my cactus stands, especially if they aren't flowering.

 

[Tom]

Here is tox profile that may be helpful:

http://cdpr.ca.gov/docs/emon/pubs/fatememo/pyrethrin_efate2.pdf

Thank you Steve. Reading now.

 

[Iochroma]

It looks like the pyrethrin is essentially gone after 5 hours in sunlight. This has been known for a long time, and the application will be most effective if sprayed at dusk. Evening applications also reduce the potential threat to bees.
The product "Provent-a-mite" was specifically formulated to be safer for reptiles; I would seek that out if i were going to use a pyrethroid compound.
I am still researching imidacloprid safety...

 

[Iochroma]

There is very little on the topic, but this is pretty damning:

Imidacloprid induces morphological and molecular damages on testis of lizard (Podarcis sicula)
Author:
Cardone, Anna
Source:
Ecotoxicology 2015 v.24 no.1 pp. 94-105
ISSN:
0963-9292
Subject:
Podarcis, adults, apoptosis, dose response, environmental exposure, estrogen receptors, imidacloprid, lethal dose 50, males, messenger RNA, sex hormones, spermatocytes, spermatogenesis, steroid hormones, testes, wall lizards
Abstract:
The insecticide imidacloprid was evaluated under laboratory conditions in the adult male Italian wall lizards (Podarcis sicula) to assess its potential toxicity. By an acute oral test, LD50 was 503.76 mg/kg. Changes in spermatogenesis, plasma sex hormone levels and androgen and oestrogen receptor mRNAs were analysed by subchronic test and simulated environmental exposure. 15-days subchronic test, in which lizards were orally dosed on alternate days at 0, 10, 50, 100 mg/kg bw, showed a dose-dependent changes of testicular architecture and an increase of apoptotic processes. In a 30-days simulated environmental exposure spermatogenesis was arrested at secondary spermatocyte level and only few primary spermatocytes were TUNEL-positive. In all experimental groups imidacloprid was able to decrease both the level of sex hormones and the steroid receptor mRNAs. The results demonstrate that imidacloprid affects reproduction function of male lizards therefore precautions must be taken to minimize the harmful effects of this compound.

My take away from this, is that it is not very toxic to this lizard, but did damage to the reproductive system at high (unlikely) doses.

 

[Iochroma]

Have you considered a neem product?
https://www.planetnatural.com/product/azamax-azadirachtin/
I would not use a neem oil in a hot climate, but the extract should be safe.

 

[DancesWithDinosaurs]

Personally....... Use whatever pesticide that doesn't kill bees and will do the job and meanwhile buy their cactus from the store until the bugs are GONE and the poison is degraded and gone. I don't really see any of these half measures getting rid of these miserable little pests.

Tests prove 1 year after spraying Round Up, the soil and crops grown 1 year later, STILL contain Glyphosate. My neighbor spouted your mind set for year's. Claiming how safe Round Up and Dursban were. When he got kidney cancer, the fisrt question the doctor asked was "Have you used pesticides or weed killers?" Thankfully he is half mile down the road. He did not enjoy getting chemo injected up his penis and the multiple chemo and radiation treatments to save his life. They are fully integrative pest management now. We live in the country. Every time a chemical is used, there are consequences.

 

[K8E K]

When I worked at the conservatory and botanic gardens we had a miserable time with these as well, especially on the Opuntias and a few of the Echiverias. We used IPM as much as possible, only spraying in the palm house where we couldn't get up high to physically address pest issues. The only way that I know of to manage the the mealy/whitefly/scale naturally is to keep the plants less stressed (I second what Yvonne G says, more water is usually it with the Opuntia).

If you can manage with the number you have, have one massive cleanup weekend: hose off, spray with a bio-insecticide (neem oils, alcohols, hydrogen peroxides are used in organic farming, and I'm not well schooled in this area. Sounds like the convos above cover that with more expertise). Then follow up with a toothbrush around the glochids, if your variety has them (yeah, I know. but the mealy can really get in there). Basically, just knock them out as best you can, they spread very efficiently...then maintain.

We never had good luck without actually physically scraping them off, and then trying to nail the care so they didn't return in such force. I've had one or two in my "experimental" group that for the last five years haven't had a single mealy, while I have several others that do. It is not at all a controlled "study", it's about as random as my other plantings, but the one thing I have been intentional about is giving them more water, which they seem to like. Essentially, allowing them to *just* dry out before more water.

Not sure if that's possible for you, but it's helped my patch. To be fair, I have a few little free laborers here that seem to enjoy getting to scrub cactus with toothbrushes Not sure how long that'll last, I'm sure they'll need therapy later in life.

 

[K8E K]

Tests prove 1 year after spraying Round Up, the soil and crops grown 1 year later, STILL contain Glyphosate. My neighbor spouted your mind set for year's. Claiming how safe Round Up and Dursban were. When he got kidney cancer, the fisrt question the doctor asked was "Have you used pesticides or weed killers?" Thankfully he is half mile down the road. He did not enjoy getting chemo injected up his penis and the multiple chemo and radiation treatments to save his life. They are fully integrative pest management now. We live in the country. Every time a chemical is used, there are consequences.

Yeah, Glyphosate is nasty stuff. I'd avoid at all costs.

 

[K8E K]

Maybe start a hippie natural dye company with all your Cochineal? Look, I'm being so helpful!

 

[SteveW]

Thank you Steve. Reading now.

Hey Tom. I don't think I followed up. How's your cactus?

 

[Loohan]

Spinosad?

https://en.wikipedia.org/wiki/Spinosad

 

[Tom]

Hey Tom. I don't think I followed up. How's your cactus?

Same. I decided to just keep spraying the insects off with water. I'll just have to keep after it once or twice a week in summer.

I just don't trust any of the chemicals in this situation.

 

[MichaelaW]

Same. I decided to just keep spraying the insects off with water. I'll just have to keep after it once or twice a week in summer.

I just don't trust any of the chemicals in this situation.

I'm now dealing with this and it is destroying my cactus.

 

[Tom]

I'm now dealing with this and it is destroying my cactus.

Its time consuming, but use a good hose nozzle and spray them all off once or twice a week. This kills most of them, keeps them at bay, and also keeps your cactus watered. Healthy, watered cactus seems to be able to stand up to them better.

I never did find a chemical insecticide that I felt comfortable using.

In your more humid climate, the cochineal eating mealy bugs would probably survive and do well. Its too dry here for them here.