Scale Infestation

[scy]

I posted about a cymbidium that had scale among other pests. I have gotten rid of the spider mites, fungus gnats due to all of your helpful suggestions. However, the scale problem has gotten worse. I have tried Neem Oil for a few weeks and going through each individual leaf with alcohol (threw my back out in the process as it had so many leaves).

I did my first spraying of Malathion (spraying everywhere to cover all the leaves, undersides and the bulbs (what I could reach) on Saturday morning after watering. Now the scale looks even worse and is absolutely everywhere!

I ordered some fine bark mix and am planning to repot it. The aerial roots are showing new root branchings and the plastic pot is starting to become deformed, so I think it's time to pot up in a slightly larger pot. I have no idea how to divide and given the scale infestation, I don't want to weaken it further so I will pot up to an 8" pot.

I am planning to spray once a week until it's gone, but since the scale is everywhere now, what should I do?

1. Should I keep using the Malathion, try using Bayer Advanced Dual Action Rose & Flower Insect Killer, or use both? The label says that one of the ingredients is the same chemical as Merit.
2. I was hoping to repot soon since I saw the root branching and thought it would be good timing to do it now. Is it ok to repot when I have the new bark (and prepared through proper soaking) or should I wait until all the scale is gone?

The scale infestation is so severe that it looks like it has dandruff. When I was watering today, it saw scale on almost every leaf. Is this a lost cause?

[Tindomul]

First and formost, mechanical removal is a must. Remove as much scale as you can find. If you really love the plant, spend an hour doing it, put off to a side come back two or more hours later with fresh eyes and do it again. Once you can't find any more clean the leaves with alcohol using a napkin. Apply a little pressure when applying so that its almost like you are scrubbing off whatever is on the leaf, but don't hurt the leaf. You can use insect spray to kill anyone you missed, and do the whole thing again in a few days, no more than a week later. Keep doing it at least once until you don't see any more scale for at least one or two months. Its a lot of work but really the only way to do it. Scale I believe is the worst of all the pests I have encountered. I have successfully fought off mealy bug, mites, thrip, millipedes in one or two treatments, but scale is a special kind of enemy. Good luck.
PS, I use dish olive oil with vinegar and sometimes dish soap. Don't use too much olive oil as it can prevent the leaf from breathing and will die. I found out on my mint that soap also kills if left on the leaf too long.

[beezermommy]

Hi-I also have been fighting a scale problem for about 1 year. Was working then. I am now home (unemployed) and started the battle again. I also have 3 dogs so try not to use heavy duty chemicals. I have been scrubbing, scrubbing and scrubbing with alcohol and lots of hands-on. I also spray 1xweek weak fertilizer, ivory liquid dish soap and super thrive. Hoping this will help. Living in South Florida I cannot use any time of oil now (too hot). Good luck to both of us.

[DavidCampen]

Originally Posted by beezermommy

Hi-I also have been fighting a scale problem for about 1 year. Was working then. I am now home (unemployed) and started the battle again. I also have 3 dogs so try not to use heavy duty chemicals...

Pyriproxyfen is an Insect Growth Regulator that can be used for control of scale. It should be of very low toxicity to mammals.
http://www.valent.com/agriculture/pr...e&pageid=44083
The Use of Pyriproxyfen in Dogs and Cats

[fishmommy]

I am reading this thread with great interest. I have been fighting a mild scale problem on one of my catts for about a year with only limited success. I threw out one catt last year that had it, and am about to throw out the other.

I suggest quarantine of any affected plants as this stuff is contagious! Good luck fighting it!

Personally, I never look at a plant the same way once it has had any scale. The only way to be sure your collection is not at risk is to completely quarantine (including any watering cans and supplies)

[Daethen]

I had a huge scale problem that came with a bunch of orchids I ordered. I used malathion by making a huge batch and soaking the plants bare root for 5 to 10 minutes each. Then potted them in clean pots with fresh medium. A couple of weeks later I soaked the plants again in malathion medium, pot and all. I spent some time before the second soak going over the plants with alcohol and a tooth brush. Haven't seen any since.

[ezil]

I agree with fishmommy. Quarantine that plant AND wash your hands each time you handle it. I have the nasty habit of checking a plant that has "something" about 3-4x a week, and fuss! When I see 1 scale, I know there are more. As soon as I see 1, I have to squash it, then clean the whole leaf and stem with alcohol. However if you have any eggs/little ones under your nails, you can still contaminate other plants. It's a long battle, but worth it. I also suggest repotting in fresh medium if you haven't done so. Good luck.

[Junebug]

A few years ago some of my young cattleyas were severly attacked by scale. I didn't know about treating with alcohol at the time. The scale was on the underside of the leaves, the pseudobulbs, the rhizomes, and roots. They were in such small crevices that I couldn't imagine how to remove them. First I removed the entire plants from their pots and gave the entire plant and roots a good soaking in Orthenex. Then I remembered I had an old electric water pik destined for the thrift shop. I used the jet action of the waterpik filled with orthenex to remove every trace of scale I could find. Then I repotted those poor plants into fresh pots with fresh medium and quarantined them during recovery. I retreated them with Orthenex every 7 to 10 days for the next 3 months. All of the plants survived but it took them a long time to recover.

[Gin]

I use Bayer Tree an Shrub as a drench 1 Tbs. to a gallon of water flood the pot bottle says it kills for 30 days but I don't believe it I use then wait 2 weeks then use again . Tops are sprayed with Safer insect soap spray to kill ones on the leaves it takes a bit for the Bayer to enter the plant system . I do not have any animals or kids to chew on the plant

[scy]

Tindomul: I tried your way today and took breaks as suggested. I removed as much as I could see and then brought it outside and sprayed it again with Malathion. While it was outside, I noticed there was a lot more that I didn't get to. Unfortunately, my back went out again so doing this again every few days will not be an option for me. I did find some big brown spots on the leaf itself so I scrubbed it with rubbing alcohol soaked cottonball and even dug into it with my fingers (through rubber gloves). I think it was a giant scale, because it oozed white stuff and parts of the outer brown part was coming off and onto the cottonball. It looked like the same stuff that was picked up by the cottonball on other leaves. However, I couldn't get the actual brown part off. It is really stuck on there. Thanks for the suggestions!

fishmommy: I'm sorry to hear that you are having scale issues too. I really hate scale! I have been seriously debating whether to throw the cym out, because this is now the 2nd time I've thrown my back out over this. I love my orchids and hate to throw it out if it's not dead, but as I see it, the scale is winning 4 vs 1. I did wash my alcohol bottle and other bottles with some antibacterial soap so I hope that is good enough.

Daethen: I'm in the same boat. I ordered this cym and it came with multiple pests. I got rid of the others but the scale is the worst! I'm not sure what kind of container I can use to dunk this cym. It's about 30" high and in a 7" pot. I plan on repotting into an 8" pot either sometime this week or early next week. I don't really have a bucket that large. Any suggestions on how I can dunk the whole thing? How did you dispose of the liquid from the dunk? The label says not to pour it down the drain. Do I have to rinse this off the roots later? Do I need to worry about root damage?

ezil: Thanks for the warning! I wore rubber gloves and washed my hands afterwards. I do the same with my other orchids too.

Junebug: Doh I wish I had an electric water pik now. The pipe broke outside and I can't even attach a hose. How did you dispose of the liquid used in the dunk?