Woolly Adelgid Problem Question ?

[Robert11]

Hello:

Live in New England, outside of Boston

Have a question about Woolly Adelgid bugs and Hemlocks:

Have a massive Hemlock in backyard that, for the first time I think, is showing several "leaves" on various branches which have turned an orange color.

Looking at them closely, I can find no evidence of white spots, white sacks, etc. on either the tops or bottoms.

Can anyone explain what might be happening ?

Water deficiency, time of year, etc. ?

Think it might be a Woolly Adelgid Problem, even without my being able to see any evidence of ?

Much thanks. Really appreciate the help.

Bob

[Zing]

As they age, Hemlocks will shed some of the lower branches. Nothing to worry about. The WA white "stuff" is pretty obvious. Google will provide many photos.

Check for mites. You'll need a 10x or better magnifying glass (shake the leaves over various colored papers, or contact your county extension agent. Have not heard of viruses, fungus etc. affecting Hemlocks, but that could be a remote possibility.

Hemlocks like somewhat moist soil (they're often native to streambanks), but I wouldn't think that would be your problem - hasn't NE had two unusually rainy seasons in a row?

If you have a WA infestation, get on it fast (probably next Spring). Hort. oil at the right time will do the trick, but watch out for a secondary infestations of mites if the tree is stressed. Make sure the arborist has a rig w/ a boom that will reach ALL of the tree, and spray both sides of the leaves. If you do have WA, notify any neighbors who may have Hemlocks. It attacks concentrated groups of trees.

Good luck.

[Beecrofter]

Hard to say, bring a sample to the extension center or a decent garden center. A good sample will show a transition from healthy to what you consider to be abnormal.

[Ann]

"Robert11" expounded:

Although it's rather late in the season to be showing winter damage, we did come through an awful season last winter, many evergreens were stressed.

As far as the woolly adelgids go, they're fairly obvious, they look like little fuzzy cotton masses on the undersides of the green needles. Hort oil in the early spring is the first line of defense, then followup applications of sun oil in the year if applicable (sun oil is lighter than hort oil and can be used later in the season, although I don't think you should be applying it in the heat of the summer).

[Beecrofter]

How many horsepower do you need to spray the hort oil to reach all parts of a 65 foot hemlock ?

[Ann]

[e-mail] (Beecrofter) expounded:

What difference does it make if you want to save the tree bad enough?

[Beecrofter]

I was just curious how you were going to get the spray coverage up there without hiring an arborist with a large bucket truck and powerful spray rig.

[Ann]

[e-mail] (Beecrofter) expounded:

I've got a home sprayer that I do my cherry tree with, it's about

35-40' high. I'm about at my limit. I would hire an arborist, though, if I wanted to save the tree bad enough. Unfortunately around here there are many, many native hemlocks, they don't stand much of a chance :o(

[Beecrofter]

Where I was headed with this was the labelling change that allowed the use of the systemic imidacloprid marketed as "Merit" to be used to control the hemlock woolly adelgid. It is applied under the trees drip line and taken up into the plant tissue. Be careful to follow all the label directions, this pesticide is very hard on pollinators and beekeepers. It is especially hard on honeybees when used as a turfgrass grub control becuase it ends up in the dandylions and clovers visited by the bees.

[Ann]

[e-mail] (Beecrofter) expounded:

I see. Well, rest assured, I don't do anything around here that might harm honeybees or other pollinators! I still have that organpipe wasp nest remnant on my front chimney to remind me of foolishly killing before learning.....;-(