Douglas Fir dropping green needles in May

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Diana Lind

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I noticed quite a lot of Fir needles on the ground which is unusual for our tree. It is a big one, probably at least 50 years old. There are other Fir trees close by without this issue.

It's May, and all the trees including this one have bright new growth. BUT, this tree is also showing dry brown Needles in sections of all the outer main branches. I am afraid this is a symptom of drought. I don't see any markings on the needles which make it look like a disease.

Any advise on how to keep this tree alive or what to expect?
 
Lots of trees got stressed from 2 hard winters and hotter than usual summers in a row in my area.

If you've had a significant lack of moisture in your area over this past 6+ months, then it likely needs water. A 50' Fir tree will consume a lot of water. Might also be a change in the water table. Barring that, there may be something under the soil that is affecting the roots, but that's hard to tell.

If you've got a hose and lots of water supply, worth a try giving it a good, long, deep drink. It would take at least a few hundred gallons at the drip line to make a dent, and some time before any change will show up.
 
Any new construction near you? Here, every 1/2 acre or more a developer can glotch onto gets 4 to 8 houses per acre or more packed in.
And of course, the omnipresent storm water pond, which changes the water table.

Lots of construction near me, one year a fir dropped all its green cones, this year one fir kept last years's cones and just dropped them last week!.
Have more than 100 over 100 YO firs on my place just south of you, there is always one that is acting different than the others.
Big spurt in all the new growth at the tips the last 2 weeks with the warm weather here, likely a big factor in your fir dropping needles.
 
Could also be signs of root rot starting to take over.


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Here is a link to an article that you may well relate to about Doug Fir with issues in May! It is about "Solving Sick Tree Mysteries". Good Luck!

"Now for the heat. We had an early heat spell in May, but exactly when was it? For this, I needed to look up temperature records, so I went to the Oregon Climate Service website, which houses records weather station data from across the state (including from OST volunteers!). The nearest station with daily temperature data was ten miles away, at the Scappoose Airport. On May 13 and 14, there was a high of 88 degrees, which ties the record high for those dates. While that’s not considered extreme heat, it certainly is extreme for that time of year. And it happened very soon after Douglas-fir trees had broken their buds.

So my theory? The few trees that looked scorched were among the budbreak “stragglers” – that is they were among the last to break bud, and probably did so less than a week before that hot weather. That’s why they were the only trees that were damaged – because their needles were still very young and tender."
 
I planted a large number of Douglas fir trees years ago - they all eventually got needle cast and starting losing their needles - as I drive around I see this happening to these trees around my area - for a couple years I tried spraying them but it got to be too much work and expense - it is a shame because these trees are beautiful - google needle cast and it tells you what to look for
 
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