These two green 6 inch long douglas fir branch tips were two of hundreds carpeting the ground under a 50 foot high Douglas fir last week.
I believe there is some type of a boring insect which invades the cambium right at the point of break-off. But I couldn't distinquish what exactly invaded.
Could it be Cooley spruce gall adelgid [1] or P. ramorium [2]? Problem with both gall and ramorium is that the foliage drops off brown.
The ones I viewed on the ground were all green. Is this just a winter snow and ice condition? I don't think so because other nearby firs did not show same carpet of green tips on the ground.
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