Stubborn scale on Nelly Isler - Orchid Board

ula · #1 01-06-2015, 08:58 AM

Hi,

I've been trying to get rid of scale on my Burr. Nelly Isler (have I written the name correctly?) for a month and a half now alternating between insecticidal soap, rubbing with alcohol and horticultural oil. I treat my orchid 3-4 times/week. Every time I get some of the scale off, but the rest seem to be quite happy at their "locale". It's a small plant still, so I was wondering if I could just soak the whole thing in one of the insecticides mentioned above, or is there something more effective I should be using, or it just takes more time to get rid of these buggers? Can you please share your experiences?

jcec1 · #2 01-06-2015, 10:00 AM

I find that scale will always get into nooks and crannies that contact insecticides miss. I use a systemic insecticide, not sure what is available in Canada, but that should solve the problem.

silken · #3 01-06-2015, 11:02 AM

I've battled with scale on several occasions. It is persistent and I remove the obvious ones, but then pull out the big guns. In the summer at Canadian Tire you can buy Malathion. Trouble is I doubt you can get it at this time of year. It is a contact pesticide but quite effective if used once a week to keep getting the eggs that hatch. It stinks, but I will live with that and spray them in the garage, outdoors or wherever, not in the house. Then let it dry totally before handling it. Use rubber gloves on hands and do not breath it.

Our society also purchased a large agricultural supply of granular Merit and our members can buy small amounts. It is the only systemic in Canada that I am aware of to deal with scale. It contains imidacloprid which is found in the Bayer 3 in 1 Rose spray that the Americans seem to use on orchids as a systemic. I am not aware of it being available here. There is a liquid Merit but I don't know where to find it in Canada.

Be sure you have your plant well isolated from any other plant. The newly hatched scale look like white fuzz or white mould, but the females mature and become a round hard scale under which they lay more eggs. In a real bad case, I have un-potted (they will be in the media also) and soaked the entire plant emerged in a Malathion bath. That way it can get into all nooks and crannies. I hate scale and have a greenhouse with well over 100 orchids so I do not want an epidemic!

I would not soak the roots of your plant in rubbing alcohol. Not sure what horticultural oil would do, but I wouldn't want oil on the roots if it were mine.

ula · #4 01-07-2015, 08:47 AM

Thanks jcec1 and Silken,
I do have some Malathion, but I have to scrap that idea until high spring (my garage is detached and unheated). It doesn't help that this orchid is very stressed, trying to grow new roots- got it at a show in October, looked fine for a while planted in what looked to be fresh sphagnum, but when I investigated (upon its decline) it turned out the sphagnum was wrapping something that was so decayed, that it had mud consistency. Plus some leaf spots I paid no attention to turned out to be scale...

silken · #5 01-07-2015, 09:46 AM

I guess if you had to, you could put the plant in a bathroom, spare room, or basement in a garbage bag. Then spray it and the media well with Malathion, close the bag off for an hour and then remove the plant and let it dry. If you have a place where you can contain the smell and keep it away from pets or children. The smell leaves once things are dry. You will likely have to repeat in a week in case more eggs have hatched.

Or toss it and try again. Nelly Islers can be found occasionally. Can I ask what vendor sold it to you, so I don't buy from them? If it wasn't Paramount in B.C., they usually carry this one and you could order one in the spring to replace it. Or you could see if the vendor would replace it with a healthier one.

ula · #6 01-07-2015, 01:38 PM

Quote:

Originally Posted by silken

I guess if you had to, you could put the plant in a bathroom, spare room, or basement in a garbage bag. Then spray it and the media well with Malathion, close the bag off for an hour and then remove the plant and let it dry. If you have a place where you can contain the smell and keep it away from pets or children. The smell leaves once things are dry. You will likely have to repeat in a week in case more eggs have hatched.

Or toss it and try again. Nelly Islers can be found occasionally. Can I ask what vendor sold it to you, so I don't buy from them? If it wasn't Paramount in B.C., they usually carry this one and you could order one in the spring to replace it. Or you could see if the vendor would replace it with a healthier one.

I like your bag idea very much, I think I'll try it in my furnace room (nobody ventures down there and it's warm). I don't want to reveal the vendor, because it was one of the bigger, American ones, so it might be something they got from a wholeseller for resale not being aware there is a problem. The plant looked super healthy at the time of purchase, and I took no photographic evidence to back up my claims, so I dare not ask for a replacement...I really love the flowers on this one, hence I'm reluctant to chuck it.

silken · #7 01-07-2015, 01:52 PM

Quote:

Originally Posted by ula

I like your bag idea very much, I think I'll try it in my furnace room (nobody ventures down there and it's warm). I don't want to reveal the vendor, because it was one of the bigger, American ones, so it might be something they got from a wholeseller for resale not being aware there is a problem. The plant looked super healthy at the time of purchase, and I took no photographic evidence to back up my claims, so I dare not ask for a replacement...I really love the flowers on this one, hence I'm reluctant to chuck it.

Good luck. Some seaweed would encourage root growth.

astrid · #8 01-22-2015, 06:55 PM

This isn't scale on your Nelly Isler!!

I have had ... 3 nelly islers so far (one died in a watering disaster) and I thought they ALL had scale.

However it is not scale at all. It is a type of edema (swelling of water in the cells) of the plant. So these brown spots are NOT scale, they are blisters and have formed "scabs." Scale should be easy to remove with simple wiping, and these just don't come off. Don't put your plant through the stress. If you look on my youtube channel you can see that in all the videos about my nelly islers, they have those spots on the leaves, and none of my other plants do.

Nelly isler videos: https://www.youtube.com/user/artiste...ry=nelly+isler

Other orchid videos:
https://www.youtube.com/user/artiste...h?query=orchid

My boyfriend just bought me another one for christmas, and that one has the same brown spots as the others did, and I didn't bat an eyelash at it because I've seen it on my Nellys before.

Really!

Every single Nelly Isler I've bought has this on some of the leaves, and it happens due to too much water being provided in cool temperatures, and there is a paper on it.
Here is the link: http://staugorchidsociety.org/PDF/Ed...ySueBottom.pdf

It says, "Sometimes
edema is mistaken for scale, though scale
can easily be rubbed off with alcohol and
a Q tip."

And that is true. The brown spots never spread to my other plants even though I house them close together, so these are just little blisters. I promise! I just think it's a problem with this particular plant.

ula · #9 01-23-2015, 08:11 AM

So you and me both, huh

? It's part of the hard learning process. Too bad your post comes about 2 weeks late...because I resorted to cutting off the offending foliage-as we both know now, that nothing would work for this offending "scale"

. I would post pics, but I'm ashamed to show the results of my ministrations. I have a new pb growing out, so I'm hoping for a happy ending.
Thanks Astrid!