Bonsai Study Group Forum

General Category => Evergreen Bonsai Discussion => Topic started by: Elliott on September 20, 2011, 01:00 AM

Title: scale on blue atlas cedar
Post by: Elliott on September 20, 2011, 01:00 AM
Hi all
 About 5 months ago I picked a nice blue atlas cedar from an older club member who had to part with his collection. He origiany got the tree from George Yamaguchi in the the early 80's or late 70's as a little whip.
 I started to notice some needle discoloration and thats when I dicovered it had a scale infestation. very tiny little brown bastards. Not the fuzzy type. I hit it with bayer 3 in 1 systemic that has a weak fertilizer, an insecticide and a fungicide. This stuff works wonders on all my material from pines to oaks to ficus. It killed some of the scale but I still find alot of them that are still "juicy" when I squish them.
 Everybody I ask gives me different advice. Blue atlas seem to be a little more sensitive than alot of other trees, so I don't want to kill it. I've been told to use an oil treatment, then wash it off the next morning, I've told don't use oil at all (I live in a hot climate, it will be close to 100'F this week here), Also soapy water and and using a toothbrush to physicaly remove them.
 Any ideas from you guys with blue atlas experience?? ???
Title: Re: scale on blue atlas cedar
Post by: MatsuBonsai on September 20, 2011, 05:15 PM
Are they active this time of year?  I don't think the Bayer will penetrate the outer shell at this time, and I'm not sure they're feeding this time of year for the systemic.  Can you provide a picture?  What does your local extension office say? 
Title: Re: scale on blue atlas cedar
Post by: Dave Murphy on September 20, 2011, 05:43 PM
I'd squish them...
Title: Re: scale on blue atlas cedar
Post by: plantmanky on September 20, 2011, 06:21 PM
The best thing for getting rid of scale is to spray with horticultural oil and water.  It just takes a couple of applications about 4 days apart and whooshhhhh  there gone.  The oil clogs their breathing and they die of suffocation.  I usually use 4 tablespoons of horticultural oil to a pint of water and spray it on by hand.  You definitely want to take care of that right now as scale will over winter on your trees.  Particularly if it's a mild winter.

ta ta for now
Title: Re: scale on blue atlas cedar
Post by: Elliott on September 20, 2011, 11:33 PM
Matsu.. the bayer is a systemic that is absorbed by the tree when it takes up water and the bugs injest it when they feed on the tree. It has worked very well on scale on my other plants in the past. This scale is different. they are about the size of a large grain of sand and are brown. Insects are very active here in so california almost year round. In fact, this time of the year here is almost as bad as spring for pests. It was about 90' f today. They are to small and to numerous to squish by hand. The atlas needle bunches are very brittle and snap off if you even look at them wrong!
 monkey.. I heard its a bad idea to use oil on blue atlas. Maybe some agricultural soap my do the same thing. None of my other trees have any pests. I have junipers, oaks, craype myrtle, elm, melaleuca (paper bark tree), and hackberry all in close proximity.
 I will spray a small bunch of needles with the soap and if the the needles look ok in a couple of days, I will spray the rest of the tree. I was thinking some very diluted lyme sulpher might be in order if I have no other recource. I will let you all know. Thanks!!
Title: Re: scale on blue atlas cedar
Post by: MatsuBonsai on September 21, 2011, 08:33 AM
Yes, thank you.  I would think that if the Bayer isn't working at this time of year that they are not active at this stage and/or the Bayer is not effective at this stage in the insects life cycle.  Even in California I would think the life cycle of scale would be the same.

My local extension office suggested insecticide in Spring while they're still in the crawler stage, and dormant oils in Winter.  I'm curious to know what yours has to say, and if they can identify the type of scale affecting your tree.
Title: Re: scale on blue atlas cedar
Post by: John Kirby on September 21, 2011, 06:27 PM
OK, if they aren't active at this time of the year, they aren't feeding, which means they are pretty much just a distraction, and the harbinger of activity in the spring. I use merit (imidacloprid) on my Blue and green atlas cedars with no negative effects for the past 5 years, before that I used disyston which was much more aggressive. If you get the systemic into the tree as it is preparing its spring cycle you can get the tree ready for when the active and mobile form of scale hatches and starts to feed. If you don't like looking at the ones on the tree now, the "squishing" suggestion is a very good one and couple with fall needle re oval will give you a great chance to look and work the tree over.

Greetings from Tianjen,
Title: Re: scale on blue atlas cedar
Post by: Elliott on September 21, 2011, 10:46 PM
They are active because when I do squish one. there is a yellow spot on the needle. They are to numerous and tiny to squish by hand. It would take 2 days which I actualy would be willing to do, but I would cause to much damage to the tree. The insecticide in the bayer is the same one you mentioned in your post.  a couple of months ago the bayer worked, now it doesnt. They must have built up an immunity. I sprayed on a horticultural soap on a needle bunch yesterday. The scale on that bunch were dried out today. I will wait till fri and if the needles I sprayed don't look like theyare having a bad reaction to the soap, I will spray the whole tree.
 if that doesnt work, my next plan of action will be illustrated by the following joke: How do you make a blue atlas cedar sound like a dog?? You dowse it in gasolene, throw a lit match on it, and it will go "WOOF"! ;D ;D
Title: Re: scale on blue atlas cedar
Post by: John Kirby on September 22, 2011, 04:24 AM
they don't get immune to it, it is a nicotine based neurotoxin, they just aren't feeding. Get the granular form and put it on the soil. I find it works much better, longer, and there is no chance of phytotoxicity. Is sold as a lawn care product, I buy it in 40 lb bags. John
Title: Re: scale on blue atlas cedar
Post by: Elliott on September 29, 2011, 11:17 PM
well, I ended up spraying an agricultural soap on the tree followed by a light scrubbing of every inch of the tree with a tooth brush that was dipped in an organic, plant pesticide oil that is based on fish oil. That was about a week ago. The scale all seem to be dry now on the few I find. The tree has a sickly color a little bit, but that's probably the oil or soap on the needles. I have sprayed the tree a few times with water 24hrs after treatment.
 Lets see what happens in the next couple of months as we go into fall (although it has been in the upper 80's and low 90's here lately). Thanks for everybodies input.
Title: Re: scale on blue atlas cedar
Post by: rockm on September 30, 2011, 05:35 PM
FWIW, I've found that scale usually is a symptom, not the primary cause, of weakness in a tree. There might be something else going on...They are also a symptom of ants. Ants will "farm" scale and actually place them on trees and nuture .
Title: Re: scale on blue atlas cedar
Post by: Elliott on September 30, 2011, 11:11 PM
Thanks for the input. I'm aware of the ant relationship. This particular kind of scale is different that any I have seen. Like I said, I got the tree in early summer from a long time Bonsai artist that was retiring from bonsai. I bought about 6 trees from him and like many times when you get trees from someone who is getting to old or to busy to care for there collection, they were all in a state of neglect. All the trees were chlorotic and in bad need of re potting.
 Within just a few weeks in my yard, all the trees showed  a great improvement in health. This tree came with that scale. My early attempts to eradicate them appeared successful, but they came back. It is the only tree in my collection (approx 80 trees), that I see any scale on. I do check pretty closely and if there is some on other trees, it would be a very small amount.
 I have those little black carpenter ants everywhere whether my trees have scale or not. This blue atlas has not been repotted in probably 10 yrs, so it is weakened. I will repot it in stages. A little bit every year so it will be completely repotted over the next 3 to 5 yrs. If I did it all at once, I'm sure the tree would die.
 If the tree survives then awesome, if not, I did my best and if it stayed where it was, it would have died anyways.
Title: Re: scale on blue atlas cedar UPDATE
Post by: Elliott on October 15, 2011, 12:03 AM
Well, its been about 2 weeks since I have used the soap and fish oil treatment. The tree is getting its blue color back and I'm getting some new growth here and there. More importantly, NO MORE SCALE ;D. Its still very warm here (the day before yesterday it was 100f day during the day and it only got down to the low seventies at night), so the scale should still be active if the treatment didn't work.
BTW, I heard a rumor from my nursery guy that there is a small move afoot to ban the Bayer 3 in 1 cause its killing honey bees. don't know if its true, but I'm gonna stock up. I was lucky and got a bunch of Lyme sulphur before they pulled that (Its now illegal in California) and I don't want run out of the Bayer, its horribly convenient.