White growth spreading fast

[brujo]

Hey got a white powdery flaky growth that wipes off easily on my cacti middle of the wet season here so pretty humid! thoughts ? treatments ?

[PhoenixSon]

major scale outbreak, best to remove majority with a tooth brush. Then spray with pyrethrum

White oil works but normally causes damage to the cactus due to the oil in it.

[theuserformallyknownasd00d]

Wowsers, yep scrub away!!! You'll need to do it a few times over the mth I'd say

[Optimystic]

Goodness Brujo! If you know a good spell to banish them from the earth for good im game!

Theres alot of types of scale and I can't tell which one that is but it kinda looks like what I know to be called "Greedy Scale" cause they are not particularly picky... though i've only had problems with them on a couple of opuntias and a cereus ... I got sick of rubbing them off.. the toothbrush helps a lot. knocking them off as has been recommended will kill them, but you can't see the little crawlers so you have to keep at it for a while.. seems like every other opuntial I got from ebay came with them as a free gift, and a cereus

I have not tried this on trichos but I imagine it would be similar to cereus... during the day, a cooler part of the day but when the stoma are sure to be closed (like maybe in a shady area on a hot day) I take a 50% isopropyl alcohol, and further dilute it with 50% water and use the toothbrush wetted with it to scrape them off... I wet the brush, then shake the drops off then brush them away... a fresh brush with stronger bristles works best... so long as its warm enough the alcohol will kill them and evaporate away... I was nervous about it so I tried on opuntias first and then on the cereus weeks later, and it worked good and I see no adverse effects.. so maybe you want to spot check or something if you try that... but anyhow thats helped me a bunch.. theres stll a few that popped back but not near as bad as before and I was scraping for months... now they are pretty much hard to find, just knocked a single one off today actually (and a few little ants) it may have not even been a live one but just one that got stuck but I take no prisoners when it comes to scale

Keep the plant away from other plants, and watch out for little ants which farm them... another piece of advice is check just below the soil line,,, when I was first knocking them out, I didn't realize there were breeders hiding below the soil and once I got rid of them I was doing the alcohol thing too so im not sure what helped the most... the alcohol was something I was recommended from a cactus nursery.. they used some floor cleaner product with it but i forgot which one, sunshine something, and so I just used plain old diluted rubbing alchohol and im tremendously happy with the results... but if you have none around, by all means grab a brush and knock the little fuckers off and quarantine the plant for a bit..

Make sure to check them often, more than once per week til you don't see any for a very long time

[bogfrog]

Ewww scaleys

[cactuscarl]

I just spray them with a hose on jet setting works well for me and tends to get the ones hiding around spines which you can't get with a tooth brush. They come back so eventually I'll have to try the alcohol or pyrethrum but the hose works very well to knock them off.

I probably wouldn't spray the button as you might damage it but id use the hose to remove the scale from the stock.

[TheExplorer]

BEWARE of using commercial pyrethrum sprays on trichos as they can cause a lot of damage to the skin and potentially kill your plants. If you do decide to use it you should wash it all off and into the soil within a minute or two.

[Swiper]

Wow ! that looks bad, I've been using 50% methylated spirits and 50% water for the last month or so and have not seen any adverse effects yet. I always spray them in the shade.

Good Luck !