grand fir loss of interior needles

[Evan Sussman]

The biggest concern of this same client is her Abies grandis (Grand fir). She started noticing this trees leaf loss recently. It has lost what looks like to be 50%+ of it's foliage, starting from the inside. There is now some epicormic growth on the trunk where the foliage is particularly thin.

Root colllar excavation showed 1 tiny root with potential to girdle, I thought best to leave for now since the tree is already stressed.

Otherwise the trunk flare was well above grade and roots seems to be solid.

 

[Evan Sussman]

Here is a closer picture of a branch

 

[mrtree]

Likely a needle cast. Confirm presence by looking at the underside of the needles. Look for the presence of fruiting bodies in lines where the stomata occur. You will certainly need a hand lens but using a dissecting microscope is far better. You can also easily photograph through the microscope with a digital microscope camera. Photos can then be used for ID, sent on to experts and will be useful for your client and will show you a step beyond others.

From ID you can likey then develop a spray program, three applications of a fungicide as the candles extend.

 

[Evan Sussman]

Awesome info, as it turns out I may have access to a microscope on ground to ID these. Otherwise I made a contact at the local college with a biology teacher to use the scopes there.

I'll let you know what I find out, and I'll try to get a picture.

 

[Evan Sussman]

I finally got around to looking under the leaves yesterday with a microscope. I did not however see anything I could tell was a fruiting body. I could see many pits, and on a live leave the pit area was red/purple with something in it, I couldn't tell what it was.

hmm.