View Full Version : Hemlock trouble

Ax Man
09-27-2002, 08:45 AM
3 years ago, a client wanted some hemlocks replaced in her hedge. They appeared to be scorched on the windward side, and also had the competition from a 30yr old Norway maple near by.(they are now under its dripline)

I replaced them, warning the customer of the distinct possibility of thier death due to the proximity of the maple, but she wanted them badly.
Needlessly to say they are coming out again this week.
brown and some with no needles at all.

The Maple has what appears to be leaf spot, and the twigs of some of the hemlocks are blackened.
Has anyone noticed a problem with the fungus that causes leaf spot crossing to evergreens and damaging them?

I have looked for the cotton ball things and find no evidence of that, in case someone was going give me that tidbit.

09-28-2002, 10:34 AM
Hemlocks are the only needled evergreen that will do well in the shade. Should not expect any shade damage, just a lottle slower growth in very dense shade.

Have you checked for mites? This was a great year for spider mite damage to hemlocks. Also have you ruled out scales?

Is the site wet, poorly drained? No needled evergreens like wet feet. I have a great planting of hemlocks used as a screen on a site so wet that some areas cannot be mowed every week. But the hemlocks were planted in large elevated beds and mounds, with proper soil brought in for them. Over half of these plants never get direct sunlight and they all do well, except for occasional mite incursions.

If you really suspect disease, it would be best to submit a sample to your state diagnostic lab for anaylsis. Proper disease ID often requires microscopic observation.

Ax Man
09-30-2002, 07:21 PM
They get plenty of light, exposure to the west.
Feet are definitely not wet the Norway sucks all the water up.
I was wondering about blackened twigs
Are they a sign of anything?
Our local extension is useless, but I could send a sample straight to Cornell....

09-30-2002, 08:33 PM
Sending the sample to Cornell is definitely a good idea. Another way to go --- contact a good local arborist and have them come and look. Establishing a working relationship with a qualified one can really pay off over time.