Douglas Fir sudden dieback

[AJL]

Hi everyone A question from over the pond-
Hi can anyone identify what is causing sudden needle dieback on my Fir?
It has happened suddenly in the last 10 days, so far only affecting 1 branch.
No major works done to it recently other than pinching out shoot tips and its not sun scorch because the affected branch was on the shady side and not drought given wet weather here lately!
Hope its not Phytophthora??
Alex

 

[0soyoung]

I am not sure what has happened, but it is not root rot.

Douglas firs don't conform to the classic Thimann-Skoog behavior (i.e., decapitation doesn't release latent buds in Douglas firs as it does in most other species). In my experience it will kill a branch to prune off all visible buds - in other words only prune back to a visible bud, not beyond (just as advised for many spruce varieties).

Cutting/pinching new growth before bud set (following extension of the first flush) usually will result in formation of a terminal bud or bud trio, but I'm not certain if this is assured - this year I have an instance, that has yet to form any buds since 'pinching' the new growth before any new buds were apparent - it is very healthy now, but may be dead a year from now.

My trees are all quite young still. My understanding is that when they are 8+ years old, branches will spontaneously pop epicormic buds, but mine haven't yet. There my be some other effects that come/go with age. Strangely fascinating trees even when one is surrounded by a forest full of them.

 

[ghues]

Hi Alex,
Not sure why the needles are turning brown on your fir....Abies that is......the needles just don't look like Douglas fir....the needles on your tree branches are mostly all on one plane whereas Dfir needles go around the stem.
How well draining is your mix?
Cheers Graham

 

[Potawatomi13]

To begin with is NOT Douglas fir. True Fir but can't name species. Surprised Oso did not catch.

 

[0soyoung]

To begin with is NOT Douglas fir. True Fir but can't name species. Surprised Oso did not catch.

... need an emoticon for snoozin'

 

[ghues]

To begin with is NOT Douglas fir. True Fir but can't name species. Surprised Oso did not catch.

Me too as Oso is usually on his game
As I said....Abies - true fir....lots to choose from, will have to wait to see if Alex has any other info on the tree.
G

 

[AJL]

Hi and thanks for your comments You guys know your firs better than me!! -The tree was miss-identified at the nursery where I bought it @8 years ago!
The mix is quite free draining ,akadama, cat litter and loam, repotted last autumn , only light liquid feeds given this season.
Im now starting to wonder if the symptoms were from Tom Cat pee? Ive seen a stray cat spray marking his territory around here the last few days?! and now some suspicious tip die back appeared on one side of my Western Hemlock group!

 

[AJL]

Since my last post I decided to repot the tree as the soil was looking very congested - in fact the whole of the soil area was filled with dense mycorrhizae surrounding some healthy looking roots.The mycorrhizae had even clogged the mesh and drainage holes!
I only repotted last autumn using free draining mix with a small pinch of Rootgrow " beneficial"
mycorrhizae-though I never thought the fungal growth would be so prolific!

Ive caught the black and white cat again in the act marking his territory against my trees while I was out watering with hose recently....He has not been back since.... and there has been no more dieback!!!

Still dont know which species this tree is!! possibly Abies procera or Abies grandis??