Soft brown scale on my new ascosenda - Orchid Board

#1 12-12-2011, 08:09 AM

I don't have much experience with pests, but after looking at some pictures online I diagnosed my Ascda Princess Mikasa Blue with Soft Brown Scale.
Am I right?

Mostly it affected blooms, there was only one bug on the leaf.

I cut and threw away the flower stem, scraped bug from the leaf with alcohol and thoroughly washed whole plant in the water with dishwashing bubbles.
Luckily this plant was quite isolated.

Is there anything else I could do at the moment? Also would soapy water kill the roots?

Thanks a lot.

PS. Sorry, I made a typo in the post title, but cannot fix it for some reason.

jrodpad · #2 12-12-2011, 08:25 AM

I don't think you have to worry about the dishwashing detergent killing the plant so long as it's ordinary dishwashing detergent (not the stronger stuff used for dishwashing machines or the anti-bacterial stuff) and it's properly diluted and rinsed. I've had success with a solution of 50% alcohol 50% water and a drop of ordinary dishwashing soap. I mix it well in a spray bottle and then spray the solution over every inch of leaves and across the top of the potting media. When I do this a few times a week for a month or two, it seems to get rid of the problem. Also, if you see any individual bugs, you can touch an alcohol soaked Q-tip to them and they will die right away.

Good luck.

- J

Daethen · #3 12-12-2011, 09:01 AM

I agree with J. Regular dish liquid won't hurt the plant. You have done the right things so far for your plant. Keep a good eye on it. They can lay dormant (or at least hidden) for a long time and then resurface. I would keep it isolated for a while yet and look in the little leaf joints. Did you repot it as well? I always do when I find scale. Last time I had any I baked all of my clay pots to kill any eggs that may have been left behind.

#4 12-12-2011, 09:05 AM

Thanks Jrodpad.
I will do the alcohol/water spraying too. The plant is barerooted, would roots handle the alcohol/water spray?

---------- Post added at 09:05 AM ---------- Previous post was at 09:02 AM ----------

Quote:

Originally Posted by Daethen

I agree with J. Regular dish liquid won't hurt the plant. You have done the right things so far for your plant. Keep a good eye on it. They can lay dormant (or at least hidden) for a long time and then resurface. I would keep it isolated for a while yet and look in the little leaf joints. Did you repot it as well? I always do when I find scale. Last time I had any I baked all of my clay pots to kill any eggs that may have been left behind.

Thank you Jonada. It is barerooted in a vase. I washed the vase with dishwashing liquid too.

jrodpad · #5 12-12-2011, 02:42 PM

I'm going to defer to the experts on this one. I've never grown anything in vase culture so I can't really say what the outcome would be. My non-scientific understanding is that the alcohol is effective against scale because it dries them out rapidly (or more accurately replaces their bodily water with alcohol). I have always avoided spraying the root mass with alcohol, worrying that the spray would act as a desiccant and eventually dry them out or otherwise damage them in the same way as the scale. It hasn't really even an issue for me because I've only ever had to treat potted orchids, which have most of their root mass below the surface and therefore not in direct contact with the spray. That said, I have heavily sprayed ariel roots - even ones with long green active growth tips - without harm to the ariel roots or the green tips. Perhaps the safest way to proceed is to spay the foliage and one section of the roots for a period of time, taking careful note of any changes and if there are no adverse affects, then spay the whole root mass. What do you guys think?

- J

ingse · #6 12-12-2011, 03:24 PM

Scales can be a nightmare to get rid of.
I would have contacted the vendor and returned the orchid to him, because i dont think its acceptable to sell orchids with bugs that do so much damage.
Scales are the one bug i am most affraid off. A member in another forum gave up her entire collection of Phal. species because she lost the battle against scales.

ezil · #7 12-12-2011, 05:58 PM

Is this a new orchid? If so, indeed contact the vendor, explain the situation, and ask what they use against scale. If you have had this orchid for a while (if I'm not mistaken, you have mentioned it before) then the vendor really cannot be blamed. Scale happens (too often) and the best thing you can do is to be vigilant and keep the plant isolated for as long as necessary. Fortunately, scale prefer blooms and leaves over roots. Also: you grow the plant in a vase, which means that you can see what happens. I have had scale and mealybugs on my mounted sederia japonica, and have treated them the way you did. I only sprayed the roots once with the alcohol/water/soap mixture, and I still have the plant isolated. Keep us posted.

Lagoon · #8 12-12-2011, 06:06 PM

Just a suggestion about the soap - Consider switching out the dish soap for a baby shampoo, still very tough on the pests but easier on the plant, doesn't remove the protective finishing the way dish soap does.

Good luck!

Vanda lover · #9 12-12-2011, 06:32 PM

I have found that it is easier to get rid of scale on vandas and asco because insects don't really like their tough leaves. Even when I had a lot of them on some of my other orchids, the vanda only gets one or two.

#10 12-12-2011, 06:37 PM

Thank you everybody for your support. I don't think the vendor is one to blame - I bought it from the show on Oct 23, so I had it for over a month.
The plant is isolated.
One of the readers commented on my blog to spray my plant with mix of a dish soap and 70% alcohol, and then rinse. I am going to try this but maybe as Lagoon suggests with baby shampoo.
Thanks again.