Mealybug

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Agavemonger
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Re: Mealybug

#1

Post by Agavemonger »

Consistent use of rotational miticides will eliminate these, scale, & aphids readily.

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Gee.S
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Re: Mealybug

#2

Post by Gee.S »

Agavemonger wrote:Consistent use of rotational miticides will eliminate these, scale, & aphids readily.

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Rotational insecticides perhaps. Just curious, is there anything other than plants alive in these sprayed areas, i.e. ants, grasshoppers, spiders?

I was exploring a treatise a few weeks ago that examined the phenomenon of local mass extinction. And you'll never guess the object of that examination. Coral reefs? Amazon rain forest? North African desertification? Urban blight? Not quite. Try Grundy Cty, Iowa, where industrialized farming has so utterly and completely replaced anything remotely copacetic to Gaia that virtually all natural life has vanished, including native grasses, birds, insects, on and on. There is nothing alive but corn. Absolutely horrifying. Interviews with regional farmers was compelling, to say the least. One farmer's wife in particular was aghast at what had happened to their land, but the only alternative is to sell the farm and abandon the lifestyle. I know your activities are far less extreme, but wonder if you've noticed any unintended consequences.
Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

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Spination
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Re: Mealybug

#3

Post by Spination »

While reading your last post, "GMO Corn" popped into my mind right after the mention of industrialized farming, as I remembered some years ago reading something about GMO corn and butterflies dying...and then I saw the subsequent comment regarding nothing alive but corn. So, I did some searching.

First, this article filled me in regarding the issue you bring up.
http://articles.mercola.com/sites/artic ... lture.aspx" onclick="window.open(this.href);return false;

A couple of things that were eye-openers to me... Bayer's bee research facility work, and Monsanto's purchase of a bee research facility. Interesting...

Speaking of unintended consequences, I found this interesting article too
http://naturalsociety.com/herbicide-res ... er-before/" onclick="window.open(this.href);return false;
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Agavemonger
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Re: Mealybug

#4

Post by Agavemonger »

Miticides specifically designed to do battle with Eriophyoid Mites eliminate all of the minor "sucking" insects, including Scale, Eriophyoid Mites, Aphids, and Mealy bug. Although they largely do not seem to have any direct immediate effect on Snails, Slugs, and other rasping or chewing insects, or Argentine ants, I believe that they discourage interest by these insects.

I do not include any Neonicitinoids or other P.A.N. "Bad Actor" chemicals in my rotational spray program. I consider these chemicals far too toxic to the environment (and to me) to have any use in my rotational spray program anymore. Rare exceptions would be an occasional or periodic use of Bifenthrin topically to eliminate Argentine Ants, and spot use of Deadline for Snails and Slugs. I suppose those of you who have major problems with weevils could work a neonicitinoid like Bifenthrin or even Imidicloprid into a spray program in order to discourage weevils from ever taking interest in your plants in the first place. I consider spraying these chemicals directly on the plants to be the most effective route to take. This way, the chemicals get deep into the leaf bases, where they will have the greatest effect on discouraging interest by the weevils in the first place, and you are avoiding most of the toxic effect on the environment by limiting the chemicals primarily to the plant tissues themselves.

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Stone Jaguar
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Re: Mealybug

#5

Post by Stone Jaguar »

Interesting observations.

Personally, with potted plants, I have always found Confidor (imidacloprid) far more effective as a drench than a spray. Ditto with Safari (dinotefuran), but even more so. Worth noting that I am referring to actively growing, not dormant, plants.

AFAIK, neonics most negative (and controversial) impact is on non-target inverts. Like most persistent pesticides, seepage into groundwater, streams, etc when used in volumes can be problematic to lower aquatic life and thence up the trophic chain. Not sure they have been definitely called out in series of peer-reviewed studies to represent a major hazard to vertebrates, other than via incidental intoxication. Linkage to songbird population declines ignore far bigger picture issues, IMO.

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Re: Mealybug

#6

Post by Gee.S »

Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealy Bugs

#7

Post by Stone Jaguar »

Seem to recall we've been over this before. Having controlled persistent outbreaks of mealies (incl root mealies) in commercial greenhouses that had been so overrun the owners were at wits end, strongly recommend Enstar II in combo with a contact (malathion or Mavrik) and spreader-sticker to runoff. Get a good rechargable electric backpack or hand towed sprayer. All-in for the above probably just over USD 350.00, but for situation you describe, a worthwhile investment. Two or three cycles should produce desired results.

This is not a pest that is difficult to control with the right products and spray regimen. Those claiming mealies and armored scale are "impossible" to gain control over simply don't know their ag-chem. Child's play when compared to pesticide resistent two spot spider or cyclamen mites.

I use Safari in rotation with imidacloprid drenches in my own collection in the US, since I never let them get out of hand. Have not needed to resort to any tool in the greenhouse heavier than a 1.5 lt hand sprayer in years, but am ever vigilant and on them at first sign of a colony. Once they're gone, do not let them regain even a toe hold. Seasonally, thrips and aphids much bigger threat for me.

Always be aware of local laws governing pesticide use and employ common sense and proper safety gear when spraying.

Good hunting,

J
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Re: Mealybug

#8

Post by Stone Jaguar »

While a single study whose conclusions lean quite a bit on informed speculation, IME, a very worthwhile lightly-technical read for those who are frustrated by some of the causal factors behind "ineffective" systemics. The efficacy of the product, coupled with real world translocation to the "affected parts" is key.
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Re: Mealy Bugs

#9

Post by Stone Jaguar »

There is little argument that drenches involving systemic pesticides made on dormant or semi-dormant plants can be of limited value. Since my experience with worst case scenarios involved commercial setups with Cattleya orchids and all the cycad genera, it was probably easier for me to onboard and digest this limitation than it would be for the average grower.

I do not use bifenthrin, but have colleagues who spray Talstar Pro (equivalent to Bifen) in the greenhouse I'm in as a broad spectrum contact/residual and are more or less happy with the results. I would emphasize that no one at my location is controlling a major outbreak of anything. My personal experience, based on a couple decades wrestling with mealies and Asian cycad scale as a hobbyist and outside consultant is that a successful eradication program starts with a good contact insecticide in combination with Enstar sprayed to runoff with complete coverage - hence the importance of a spray rig that provides ease of use and uniform nozzle pressure - at curative label rates. Minimum two apps. Further touch up control can be provided as needed. Follow up with Safari (Dinotefuran) in rotation with imidacloprid drenches as preventive.

While I understand that these products are not available to everyone, and that some may find the cost prohibitive, I think the end result is well worth it for growers with larger collections facing a major outbreak.

I cannot emphasize enough the need for subsequent vigilance to avoid scale, mealybugs, etc from re-establishing themselves in one's collection. Once wiped out, I find that having a hand sprayer around containing a fresh solution of your prefered contact insecticide (I find Bayer 3 in 1 Advanced is a good, low-tox option in this role) or home remedy bug elixir will usually do it.
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Azuleja
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Re: Mealy Bugs

#10

Post by Azuleja »

Are the root mealies obvious to the eye?
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Agavemonger
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Re: Mealy Bugs

#11

Post by Agavemonger »

Very obvious!

They often have a pink coloration when underground.

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Re: Mealybug

#12

Post by Rimrock »

Dredging up an old thread for a slightly off-topic question. I have a problem with scale on some species. The scale attacks the tip spine area and the area where side spines hold the leaf to the central cone of the plant. The scale has a white fuzzy covering and the scale insects are small and brown. I haven't tried squishing them to see if they are red...

I have been using Bayer 3-in-1, which controls the scale if the insecticide is sprayed forcefully enough to dislodge the insects. However, the scale keeps coming back (I apply it every 3 months). The problem seems seems to be that there are always some insects left deeper in the cone, and even prying the top few leaves loose at the tip doesn't get to them. Suggestions?
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Re: Mealybug

#13

Post by mcvansoest »

I have successfully used malathion on a couple of Agaves that had what you describe. Took a number of applications and carefully peeling the leaves open to get access.
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Re: Mealybug

#14

Post by DesertDweller »

mcvansoest wrote:I have successfully used malathion on a couple of Agaves that had what you describe. Took a number of applications and carefully peeling the leaves open to get access.
This. I found a lot more success when I carefully pried open the core to get them before waiting for the leaves to open. If you get some long reptile tweezers, the 12" long jobbers, I find they work really well for delicately pushing the leaves open from the top.
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Re: Mealybug

#15

Post by Rimrock »

Ok, no suggestions about a better pesticide. A couple of the agaves with the scale infection have pretty massive leaves and a tenacious grip, so its not easy to pull a leaf loose. I wonder if I would get better results if I put some cotton soaked in insecticide at the spine tip and covered it with a plastic bag. Or maybe more frequent application of insecticide, or a stronger mix.

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Re: Mealybug

#16

Post by Gee.S »

Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealybug

#17

Post by Rimrock »

Gee.S wrote:TriStar
ok, thanks for the suggestion. tristar is on order, I'll update the thread after trying it a few times.
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Re: Mealybug

#18

Post by Gee.S »

I have been wrestling with mealies for quite some time now, and IMHO, they are just the worst. Systemics are not especially effective because plants do not generally absorb and spread these noxious chemicals evenly throughout, and mealies can move to areas where the sap they are sucking tastes less bitter (and is thus less toxic).

A larger issue is the delayed hatching thing. When conditions are less than ideal a certain percentage of mealy eggs may delay hatching for many months. That is why plants which have been treated and apparently cleansed often suffer re-infestation as much as a year later.

All one can do is inspect plants on a regular basis and treat with one toxic chemical or another as soon as discolored spots appears in upper leaves. But in the end, this is control and not elimination. I suspect the only avenue toward elimination may be disposal of infested plants.
Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealybug

#19

Post by DesertDweller »

Gee.S wrote: Wed Feb 02, 2022 5:10 pm I have been wrestling with mealies for quite some time now, and IMHO, they are just the worst. Systemics are not especially effective because plants do not generally absorb and spread these noxious chemicals evenly throughout, and mealies can move to areas where the sap they are sucking tastes less bitter (and is thus less toxic).

A larger issue is the delayed hatching thing. When conditions are less than ideal a certain percentage of mealy eggs may delay hatching for many months. That is why plants which have been treated and apparently cleansed often suffer re-infestation as much as a year later.

All one can do is inspect plants on a regular basis and treat with one toxic chemical or another as soon as discolored spots appears in upper leaves. But in the end, this is control and not elimination. I suspect the only avenue toward elimination may be disposal of infested plants.
I too have struggled with this, seems to have gotten worse over the last couple of years. I had got really liberal with Forbid and other insecticides, along with soaking in insecticidal soap. That seemed to work some of the time, but with the noted problem that a few were so far gone that nothing could redeem them, or at least not for long. If you don't start tossing plants that are too compromised, you will never beat back the infestation.

At this point, unless it's something I particularly care for, I just toss it straight into the trash if I spot a bunch of mealies. Hobbies are supposed to be enjoyable, and there's no enjoyment in dealing with persistent pests and trying to salvage an uglied up plant that you know will decline again sooner or later from the same malady. ::x
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Re: Mealybug

#20

Post by mcvansoest »

I find it really interesting how selective the infestations are. I will get it in one Agave and immediately get really worried about the plants growing close to them only for them to never get them. I make a concoction of a bunch of pesticides including the really stinky Ortho stuff that I know gets used liberally in most box stores (because of the distinctive smell). I treat plants every two weeks for a couple of months and then once a month for a couple more months before putting the stuff away till I find the next infestation.

As noted, control rather than prevention.

Interestingly, I have not had it in any Aloes and on just a few potted cacti.

My latest bad infestation is on a mangave 'tooth fairy' which seemed fine one week and then was not. It is a potted plant and the agaves and several mangaves around it are just fine with nothing going - I do treat them to the same cocktail though.
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Re: Mealybug

#21

Post by Gee.S »

Yes, it seems mealies prefer living in colonies, rather than spreading themselves more evenly throughout the garden. So they colonize certain plants, while ignoring many/most of those surrounding. They generally prefer low saponin agaves, but will on occasion try setting up shop on those with high saponin. I've also noticed that they're easily knocked down on some agaves, but keep returning (the delayed hatching thing) time and again on others.

I will also note that if white mealy stains are spotted at the base of leaves on an agave, it is in my experience unsalvageable, and should be removed.

I have never spotted mealies on any plants here other than agaves, but that could be an oversight on my part.

One final observation: mealies are more prevalent and pervasive in summer than other times of year. Seems they prefer their hosts sun- and heat-stressed, at least here in sunny Arizona.
Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealybug

#22

Post by Gee.S »

DesertDweller wrote: Wed Feb 02, 2022 5:42 pm I too have struggled with this, seems to have gotten worse over the last couple of years. I had got really liberal with Forbid and other insecticides, along with soaking in insecticidal soap. That seemed to work some of the time, but with the noted problem that a few were so far gone that nothing could redeem them, or at least not for long. If you don't start tossing plants that are too compromised, you will never beat back the infestation.

At this point, unless it's something I particularly care for, I just toss it straight into the trash if I spot a bunch of mealies. Hobbies are supposed to be enjoyable, and there's no enjoyment in dealing with persistent pests and trying to salvage an uglied up plant that you know will decline again sooner or later from the same malady. ::x
I have not tried Forbid on mealies, but did try Avid, and found it startlingly ineffective. My mealy arsenal consists of TriStar (systemic foliar spray), Bifen (bifenthrin termiticide, also found in Ortho), and Malathion. I have also begun experimenting with an especially nasty systemic drench, Dimethoate. In my experience, imidacloprid is ineffective.
Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealybug

#23

Post by mickthecactus »

Malathion was banned here years ago.
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Re: Mealybug

#24

Post by Gee.S »

mickthecactus wrote: Thu Feb 03, 2022 10:29 am Malathion was banned here years ago.
And I consider Malathion on the mild side. Very short half life.
Agave
"American aloe plant," 1797, from Greek Agaue, proper name in mythology (mother of Pentheus), from agauos "noble," perhaps from agasthai "wonder at".

"Some talk the talk, others walk the walk, but I stalk the stalk"
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Re: Mealybug

#25

Post by mickthecactus »

In a small potted collection like mine we use methylated spirits on visible mealy bugs. Works every time.

In my youth I could buy pure nicotine then dilute it and spray.
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