OH NO!!!!!!!!!!!!!!!!
i wish i can help you but i am a northern gardener and i have never grown agaves(but heard theyn make awesome houseplants)try some pesticides. i rarely reccomend it but there to be few other options

I have cochineal scale on some of my opuntia ... not to bad though, and i enjoy squishing them and coloring things ...

Grrrrrrrrrrrrrrrrr! Why do they have to exist?!? I just discovered my huge Alworthia 'black gem' was totally infested with mealies. Too far gone to even salvage any pups, just tossed it. Sometimes even pesticide won't work when they're hiding so deep down in the cracks. I also had to toss out my Dragon Tree(5" trunk), there was no way to eradicate those damn mealies! That hurt!
I need a support group to cope with the losses... or a horde of predatory insects.

Hanzrobo, have you tried a systemic like Imidacloprid on those hard to reach mealies?

Wantonamara, from what I understand aloe cancer is impossible to get rid of. I hope I'm mistaken and someone will correct me because it is pretty pervasive here in LA.

Now I must add edema to the list since I got too much rain thes last couple of weeks. We are headed into August so I should not have to worry about more unless a hurricane hits the coast.

I have cocheneal scale on the wild cactus on my land. It never gets out of hand, so something must be eating them. Maybe it is Microthrix's "texas twin" wandering around with purple fingers.

I am thinking that I need to get my truckloads of soil delivered and get these hardy ones in the soil where most if these problems will be dealt with by predator insects.

I could not find Marathon in my travels yesterday. Where do people get it. Lowe's And Tractor Supply do not carry it. Is there a systemic insecticide that one would recommend.

Yes, I think H., that these travails are to teach us patience, tolerance, (GRRRRRRR), Humility (d@mnitall#*+!!!) and the resourcefulness of the "next right step". LOL. (She laughs maniacally as she pulls out her hair)

Marathon is the brand name for Imidacloprid. Look at the labels for the active ingredients and get whatever has Imidacloprid in it. It is also known as Merit. I get mine from Ewing irrigation supply but I don't know if you have one near you. You should be able to find something with Imidacloprid in it at HD or lowes, just not a very concentrated bottle. If you have a place that caters to commercial landscape supply, they will definitely have the concentrated stuff or at least be able to get it.

I'm taking a deep breath...

Mara, you crack me up. Good luck in your battle:)

nil, thanks for the suggestion, looking into it.

Nil 13, I have heard that one can use Forbid, Avid, and liquid Sevin on Ale mite.Then one can cut out the gall. The plant can live with the gall, unsightly as it is, and spreading its vermin to all aloes and some other species too. I discovered what looked like it on an Alionopsis malherbei. I threw my plant out immediately on discovery. The plant was growing and blooming nicely. Shame. Up to that point , I was aloe mite free. I do not see it anywhere, but that does not mean it is not here. It is the agave Mite that is really getting my goat and making me more worried.. In texas, we are behind you in the "new" succulent bugs. Agave bore is just making an appearance, Both Agave mite and Agave bore are being spread through thew trade. The nurseries here are being hit hard by the stock that comes from California and Arizona. It makes growing from seed so much more attractive, but god the time it takes to get a good sized plant. I am bearing down on my 6th decade.

Nil, every time I see the MT Washington by your name I think of New Hampshire and one of my most favorite mountains, and I am confused when you talk of Californian plant problems. I guess there is another one in LA. Washington does seems to get around.

I'm going to have to stock up on some of those and give them a try.

Lol, sorry about the confusion. LA is geographically huge and full of microclimates so a neighborhood name is a little more helpful than just Los Angeles.

Nil, I have heard that using a couple of types of treatment is good to keep the Aloe mite from getting resistant.I am not sure how the procedure goes but I have heard of people treating it.

I have been treating a mealybug infestation on indoor plants with rubbing alcohol. It works well on smaller infestations. On bigger ones, I end up throwing away the plant to avoid risk of contaminating others in my collection.