Silver Maples ... chewing insects

[Dorm]

Over the last couple of years we've noticed the bark on our Silver Maples turning black or very dark grey on the trunk, limbs and branches, and along with this no or very little new growth from the trees. These are ~20' tall and diameter is about 10'. The tree problem was diagnosed as infestation of chewing insects, and the remedy was to spray the trunk, limbs et al with an oil based insecticide twice over a 2-week period.

We did a bit of research, and everything we've read says do not use oil based insecticides on maple trees, as it will kill the tree. So we're in a quandry here as to what to do, how to remedy the problem and save these 3 beautiful trees.

Any recommendations on how to kill these insects is greatly appreciated.

Dorm

 

[treeseer]

Post pictures, please. Sounds like bacterial infection not bugs. There's a lot of this around Raleigh lately; 4 of 5 white oaks at Hayes Barton church had infections, one next to the sanctuary is terminal/

 

[Dorm]

I've attached 3 pics. On the closeups of the limbs, I was told the little bumps are more like little bug tents or quanset huts, with the insects living underneath and merrily chewing away at the bark. I have sprayed this tree heavily with one dose of malathion, and from the pics you can see not much help was rendered. Any suggestions.........

Dorm

 

[treeseer]

Dorm you have gloomy scale, Melanapsis tenebricosa. All the malathion did was to kill beneficial insects. go to ces.ncsu.edu for control options; put your tax $ to work. See the link below for info on trees & turf, mulching etc. You have way too little area dedicated to tree root development. Look in your phone book under Arborists and respond to the better ad if you want an inventory/consultation at an excellent price. :angel:

 

[bushman]

Good thing for gloomy scale is hort oil. a light gauge summer oil would do the trick .ultra-fine is good one ,some have hose end sprayer.its safer than most heavy gauge oils.and will reach 15 to20.you want to spray in earlymorning or late night ,its been 95to 100 around here.read the label about temps and applying.

 

[Dorm]

Treeseer & bushman ... thanks for the advice. I called the extension office early on this year, and thus the recommendation for malathion ... tax $$ not at work Thanks for the tip on the mulching as well.

On the recommendation for horticulture oil, a couple of brands on the market are Sunspray, and Ortho Volck oil spray ... any preference on either of these or other recommendations?

 

[bushman]

sun spray or ultrafine are good products ,good luck!