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Dec 14, 2019 1:35 PM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
Does anyone have any experience controlling Aloe mites with carbaryl? I recently found a post from gardeners in South Africa that the Aloe nurseries there use Sevin to control Aloe mites and that it works really well.

https://debraleebaldwin.com/pe...

The only caveat seems to be use the spray liquid form and not the dust. Does anyone know why this could be? Dust form can kill the plant but the liquid form seems ok?

Apparently, the active chemical in Sevin has changed recently but I found a bottle of the original (carbaryl) and was going to try it on an affected Aloe. Seems much cheaper than the Aloe specific systemics. (If it works...)
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Dec 14, 2019 2:07 PM CST
Moderator
Name: Baja
Baja California (Zone 11b)
Cactus and Succulents Seed Starter Xeriscape Container Gardener Hummingbirder Native Plants and Wildflowers
Garden Photography Region: Mexico Plant Identifier Forum moderator Plant Database Moderator Garden Ideas: Level 2
Any chance of a closeup photo?

I do not have any experience with the pesticide in question.

I would recommend removing all affected growth before you even think about pesticides. I don't think chemical solutions will resolve an infestation so much as mop up the mites that might be in the area after you remove it.

My solution to the aloe mite has been either surgery (removing an affected branch) or taking out the whole plant (where surgery is not a great option). I have a zero tolerance policy once I have identified a problem. Arborescens and its hybrids seem to get mites a lot, especially on the inflorescences.

Be careful where you toss your mite-infested plants/parts so the mites stay contained. I send them to the landfill in a plastic garbage bag. My spinosissima went that way a couple of years ago and there is now an Aeonium growing in its space.

And take a look at your immediate surroundings and see if you can identify other affected plants in the neighborhood, because reinfestation is a real concern down the road. The mites have to come from somewhere.

More info here.

https://www.ncbi.nlm.nih.gov/p...

and some background info here, under Care.

The Aloes Database
Last edited by Baja_Costero Dec 14, 2019 2:50 PM Icon for preview
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Dec 15, 2019 12:33 AM CST
Moderator
Name: Thijs van Soest
Tempe, AZ (Zone 9b)
Region: Arizona Enjoys or suffers hot summers Cactus and Succulents Xeriscape Adeniums Hybridizer
Plant Identifier Plant and/or Seed Trader Cat Lover Dog Lover Lover of wildlife (Black bear badge) Lover of wildlife (Raccoon badge)
Another thing to keep in mind is that these mites develop resistance very rapidly to these chemicals so if you end up using one chemical exclusively the effectiveness can rapidly deteriorate especially if you are unable to eradicate the source of the infestation. In Agaves the preferred treatment against Agave mites is to use a sequence of different miticides.

I must say that in reading the comment by the quoted expert (Benadom) regarding how chemicals used in Africa are not tested for how they affect humans is pretty offensive especially given the whole 'Roundup' situation going on right there in California... years of exposure for people to the chemicals in roundup which are considered extremely carcinogenic by the world health organization... you'd think an expert in horticulture would be aware of things like that and would not state something that ignorant.

In Agaves there is a continual discussion between preventative and reactive treatment - should a collector treat preventatively 2-3 times a year or only treat new plants that are about to be introduced into the collection or when an infestation becomes apparent. For most people preventative treatment gets very expensive very quickly. I have some of the miticides but only use them very sparingly for plants that are new or are developing symptoms that might indicate a mite infestation.
This is a different discussion from what nurseries should do, though it is pretty clear that most Agave nurseries do not treat whatsoever or only when an infestation is apparent.

Mites can unfortunately be wind blown, so the source may be further away than you think. They are now encountered in wild Agave populations in Arizona very far removed from any nurseries which might be considered a source.
It is what it is!
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Dec 16, 2019 11:21 PM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
Thanks All good info. I found another couple of links which I found useful:

http://www.gatescss.org/Pests/...

https://www.facebook.com/48221...

https://www.gardeningknowhow.c...

Unfortunately, I do not have any closeup pictures to share. As soon as I saw the gall I bagged it up and threw it out.

I think the source is external as there are several Arborescens in the neighborhood. As Aloes become more popular around my neighborhood (probably partially my fault D'Oh! ), I guess I need to accept that a plant may get infected from time to time.

I'm torn between removing the whole plant vs cutting the gall out then applying a something like carbaryl. I guess for this first time I'm going to spray but just once or twice and then monitor the situation for the plant that was infected and other aloes that are nearby.

The other nearby aloes are also in the same wind path, they don't have any galls yet but how can I be sure they don't also have any mites in or on them?

Maybe a hybrid approach similar to the preventative but rather than every three months only when a gall has been detected and removed?
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Dec 17, 2019 10:45 AM CST
Moderator
Name: Thijs van Soest
Tempe, AZ (Zone 9b)
Region: Arizona Enjoys or suffers hot summers Cactus and Succulents Xeriscape Adeniums Hybridizer
Plant Identifier Plant and/or Seed Trader Cat Lover Dog Lover Lover of wildlife (Black bear badge) Lover of wildlife (Raccoon badge)
It is really hard to know if plants are infected unless they become symptomatic - ie. in case of Aloes the gall and or weird growth forms, and with Agaves, weird greasy leaf scarring and reduced vigor in terms of growth - on top of that some plants are very susceptible while others are not at all, but it is unclear to me if those that appear 'immune' are not still capable of hosting the mites and thus act as local sources despite not showing any outwards signs.

Another issue: some of the translaminar products if used in excess can cause a set of deformed growth on their own, so application needs to be careful and considered.

I have heard just about every scenario with regards to treatment from people: immediately chuck the plant when any kind of suspicion arises about the presence of mites (usually people with large expensive collections that tend to sell plants) combined with a pretty aggressive treatment and quarantine when new plants are introduced into the collection, to the wait and see approach to only treat when a plant is symptomatic, with differing approaches with regard to treating the rest of the plants.

So far I have been lucky and only have had a few Agaves with clear mite signs and the one Aloe which I just chucked as it was not very nice anyway. My treatment approach is to treat with a miticide once a year when I treat my Agaves against snout weevils so I create a cocktail with the miticide in it. If I see a plant that looks suspicious that is in a pot, I isolate it and give it treatment every second watering.
For Agaves in most yards Snout Weevils are much more immediate issue that mites, but I know people who bring in a lot of plants from different nurseries who have had to fight a long battle to eliminate mites from their plants, these battles easily took over a year, and in case of Agaves the damage is not easy to just cut away, so you might see the effects of the mites for years after if plants are slow growing.

So while I am sure there are 'preferred' approaches your plan may be as good as any other.
It is what it is!
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Dec 17, 2019 11:28 AM CST
Moderator
Name: Baja
Baja California (Zone 11b)
Cactus and Succulents Seed Starter Xeriscape Container Gardener Hummingbirder Native Plants and Wildflowers
Garden Photography Region: Mexico Plant Identifier Forum moderator Plant Database Moderator Garden Ideas: Level 2
Regardless of the treatment, if it's not ongoing, I would assume that the mites will return to where they were originally observed, maybe in a year or maybe later, given the susceptibility of this specific aloe. I have experienced mites with a few different aloes and my response has been different depending on the plant and the site of the infestation. Inflorescences are much easier to remove generally than stem growth. Here are the landscape plants I've had to deal with:

arborescens - regularly gets mites on the young inflorescences - I cut all the inflorescences early in bud as a preventive measure, so I never see the flowers, but that's also partly because I would like to collect seed from neighboring plants without arborescens in it (dominates hybrid offspring)

thraskii - tends to get mites on mature inflows, easily removed, never in the stem

Hercules - developed a stem infestation - I beheaded this plant and it developed a mite problem a year or so later, so I decided to remove it

humilis, nobilis, longistyla - developed stem infestations and I never gave them a second chance

maculata - affected inflow was pretty bad toward the base so I tossed this plant too

africana - only one of these ever developed a mite problem, and it was in the stem of a fairly young plant, so I tossed it

plicatilis, cameronii - a single rosette was infested on each so I removed the one branch, and none of the others has developed problems years later
Last edited by Baja_Costero Dec 17, 2019 11:53 AM Icon for preview
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Jan 5, 2020 9:38 AM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
This is all good information. Thanks everyone.

I have not done anything yet as the plant is still in bloom and unfortunately carbaryl is not mite specific so I want to minimize any havoc I wreak on the local environment bees in particular. I am also unclear on whether galls = mites or no galls = no mites, but it seems like a plant could have mites and no galls and I should probably make that assumption if other nearby plants are symptomatic.

For now I am going to leave the plant in place and monitor to see when if it ever develops another gall. It could end up acting as a kind early warning system especially if its not easy to tell whether a plant may have mites even if its not showing any galls.

I have since walked around the neighborhood and found a neighbor a couple of doors down with an arborescens that is showing some signs of mites too. Therefore total eradication is probably unlikely as I imagine our yards will continue to cross contaminate...
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Jan 5, 2020 10:06 AM CST
Name: 'CareBear'

Amaryllis Cactus and Succulents Dog Lover Hostas Irises Region: Pennsylvania
Sempervivums
I had a aloe mite infestion on a few of my aloes. Appeared after we had a very wet summer. Can't figure out where they first came from. Kept the plants away from all my collection and treated with systemic 'Imidacloprid' with no effect. Read that Sevin had limited control of spread of aloe mites so treated with Sevin liquid, with Imidacloprid and continued spraying with regular mouthwash. Treated heavily with out regard of safety of the plant due to better than throwing it away anyway. Plants almost died and didn't even water them much at all. Surprisingly next year, new growth with out any signs of mite damage. Even bloomed with out any signs. I still keep them removed from collection for safety sake but next year will be two years free, so we'll see. The miticide sold on line was just way too expensive to try.

I use Sevin now as a safety spray occasionally to keep control of any more mites or bugs along with Imidacloprid up to three times a year on all my plants.
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Jan 5, 2020 4:39 PM CST
British Columbia, Canada (Zone 9a)
I sprayed the Sevin, the original, on some succulents once. The next morning they all looked like they were made of wax and discoloured. Similar to the way neem changes the colour of plants, but much worse. I was not even sure if the plants were alive at first. They looked like someone had preserved them in a coating. I washed all the plants afterwards with soap to remove the coating. I did more damage. It did wear off with time. I will never use it on succulents again. But, it works. It kills everything. I forgot what I was treating at the time.
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Jan 6, 2020 1:42 PM CST
Name: 'CareBear'

Amaryllis Cactus and Succulents Dog Lover Hostas Irises Region: Pennsylvania
Sempervivums
When spraying succulents, remove them from bight sun. Wetness on the foliage will intensify the sun's damage. Maybe you mixed too much Sevin. I spray on a cloudy overcast day. Some times in light rain. Sheltered under a porch is best.
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Feb 8, 2020 8:56 PM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
I finally had some time to spray the plant a couple of weeks ago. Luckily its going to rain tomorrow. A downside I did not think of is that the spray was opaque.

Thumb of 2020-02-09/SDAloeTree/a438d4
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Feb 9, 2020 10:00 AM CST
Name: 'CareBear'

Amaryllis Cactus and Succulents Dog Lover Hostas Irises Region: Pennsylvania
Sempervivums
My heavy infested Aloes make great recovery, They are all blooming right now with no sign of mite damage. Of course what damage was done will not go away but new growth over took it and old stems safely removed. The growing points and crowns were heavily infested and it took years to correct.
I wonder where the mite came from in the first place. Grumbling Any new aloe purchased did not show any and it was old plants that came down with it. Living in zone 6 would kill any outside living mite.
I'm glad I tried to experiment with them and not toss them. They were common types but just wanted to see just how bad the mite is.

Thumb of 2020-02-09/Stush2019/33719a


Thumb of 2020-02-09/Stush2019/151c73

The other was an Aloe small hybrid with many pups first showed up in the bloom stock.
They are still kept in isolation just for a precaution.
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Feb 9, 2020 5:28 PM CST
Moderator
Name: Thijs van Soest
Tempe, AZ (Zone 9b)
Region: Arizona Enjoys or suffers hot summers Cactus and Succulents Xeriscape Adeniums Hybridizer
Plant Identifier Plant and/or Seed Trader Cat Lover Dog Lover Lover of wildlife (Black bear badge) Lover of wildlife (Raccoon badge)
Aside from successful treatments, climate conditions are not great mite killers - if the plant survives the mites tend to survive too. They retreat deep into the core of the plant in non-ideal conditions which is why it is so hard to treat for these successfully (without destroying the plant). A plant may be a carrier and not show symptoms for years. While they can be air blown, the most likely way to introduce them if you are not getting them from one of your neighbors is by introducing a new plant into your collection that has them and is asymptomatic.
It is what it is!
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Feb 9, 2020 9:15 PM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
Great pictures of an example of what the damage looks like.
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Feb 10, 2020 11:04 AM CST
Name: 'CareBear'

Amaryllis Cactus and Succulents Dog Lover Hostas Irises Region: Pennsylvania
Sempervivums
Thijs brings up the point why I continue to keep them in isolation. They have looked good for over a year now and possible it had one tiny mite in it when purchased that didn't show up for several years. Reason why I treat my plants twice a year whether they need it or not just in case.
Avatar for Mizmuffet
Jun 28, 2020 4:25 PM CST

I believe I have gall mites on my arborescens. I'm a newbie, so I don't know much except for what I've read here and what I've seen on YouTube. If I don't want to use chemicals, aside from tossing the whole plant, could I snip off the top where it does not seem affected and toss the stem and root? Or, that wouldn't help?

Thanks
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Jun 28, 2020 4:35 PM CST
Moderator
Name: Thijs van Soest
Tempe, AZ (Zone 9b)
Region: Arizona Enjoys or suffers hot summers Cactus and Succulents Xeriscape Adeniums Hybridizer
Plant Identifier Plant and/or Seed Trader Cat Lover Dog Lover Lover of wildlife (Black bear badge) Lover of wildlife (Raccoon badge)
You can try, but you probably should assume they are infesting your whole plant. So if you do this you'd want to isolate the plant from any other Aloes and closely related species you may have.
It is what it is!
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Jun 29, 2020 7:59 AM CST
Name: 'CareBear'

Amaryllis Cactus and Succulents Dog Lover Hostas Irises Region: Pennsylvania
Sempervivums
Waist of time if you don't use chemicals. Total plant is toast and could spread easily to other aloes, haworthia and their kin. The mite lives on the inside of the plant and travels thru the insides.
Sevin is cheap and one of the safest one's to use. It may not help. I sprayed like crazy for two years before it came under control. I still keep those plants away from my collection due to the never know what might happen next. So far this year no trace of mites. The flower stock is the first place they like to attack. Only reason why I didn't toss my plant was I wanted to see how bad those mites were and needed a subject to experiment on. I seen mite infested plants for sale at nurseries and told management so they don't give other people the trouble I read about here. It is still a mystery how my plant got it since it is one of my seed grown and no other plant came down with mites. My area up north should be mite free due to our winters.

I spray with Sevin several times a year just to be on the safe side.
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Feb 16, 2021 9:36 PM CST
Thread OP
San Diego, CA (Zone 10a)
Cactus and Succulents Region: California
Unfortunately, since I'm not sure when carbaryl is no longer legal in CA. D'Oh! (This must explain when the makers of the trade name sevin switched the active ingredient... I was wondering about that) (Amazon is up on it too try to order Carbaryl if you live in CA you get a big red banner... that translates to no way.)

Neither is Avid now or maybe ever... although many aloe collectors have sworn by it.

So I have have been forced into the expensive miticides that I was hoping to avoid... But at least I seem to have a lifetime supply since they are extremely concentrated and in a largish 250 mL bottle. I have also switched to a rotating regiment of several that all seem to be specific mostly to mites. So hopefully safer for the environment.

So far I'm trying now a monthly rotating application of:

Kontos- Systemic good for adult and larval stages. (They actually recommend rotating applications with other miticides on the bottle)

Forbid- Systemic good for all stages including eggs.

tau-fluvalinate- Never seen anyone report using this for aloe mites, but its also a miticide. Its not systemic but also controls a limited number of other sucking insects like scale, and mealybugs that have shown up recently. This is also especially bee safe as its actually used inside of bee hives to control bee mites. (who knew.)

So far so good.
Last edited by SDAloeTree Feb 16, 2021 9:58 PM Icon for preview
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Feb 17, 2021 12:38 AM CST
Moderator
Name: Thijs van Soest
Tempe, AZ (Zone 9b)
Region: Arizona Enjoys or suffers hot summers Cactus and Succulents Xeriscape Adeniums Hybridizer
Plant Identifier Plant and/or Seed Trader Cat Lover Dog Lover Lover of wildlife (Black bear badge) Lover of wildlife (Raccoon badge)
I have come to understand that when a product controls for other sucking insects the mites in question are usually spider mites. Any non systemic is going to have a hard time dealing with eriophid (spelling?) mites, which Aloe and Agave mites both fall under. They generally live inside the plant causing deformities in with different outward appearances. On top of that these mites are also microscopic whereas spidermites are small but to some extent and to people with good eye sight just visible with the naked eye. When you see a plant that has obviously been affected by Aloe or Agave mite you are not actually seeing any of the mites, just the damage they cause.
In Aloes you get the crazy looking gall like growth on leaves or inflorescences, while in Agaves the damage is less extreme looking, but still very disfiguring in bad cases, it occurs in the form of greasy looking spots over centered around dried out brown lesions.
It is what it is!
Last edited by mcvansoest Feb 17, 2021 4:15 PM Icon for preview

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