Lawson cypress dieback-any ideas?

[jonnygurkha]

Just had a call from my neighbour who is worried his Lawson cypress is dying. It has quite significant brown foliage which has appeared in the last 6 weeks particularly near the top of the tree and on one side. My first thought was Phytophthora but not sure if it is down here in Somerset and having never seen it in the flesh not sure what signs to look for.

 

Also, probably not connected, there are two phone cables which run past the tree about 2 foot away near the top and initially it looks like a utility company has 'pruned' the tree for the cables but after a climbing inspection I can see that actually the tree has grown this way and for some unknown reason has not sent any branches towards the cables.

 

I have tried to attach some photos, hope they work. Any help much appreciated!

[AlvinD]

Salt damage?

[jonnygurkha]

Possibly, I hadnt considered that. The tree is growing next to a busy ish road but there is a wall between it and the road so I don't think it would be that easy for the salt to wash down to the roots. I will go back now and see if there are any drainage holes through the wall.

[Stephen Blair]

Wind burn and salt damage, have a look inside incase the branches are damaged or part broken, if so there dying.

[jonnygurkha]

Wind burn and salt damage, have a look inside incase the branches are damaged or part broken, if so there dying.

 

The branches that have turned brown are brown all the way through. Wind burn sounds plausible to me as it is only on one side. Still not sure how the salt would have got to the roots in this case but the evidence does stack up as the gritters have been up and down a lot recently

[AlvinD]

The wee grass ledge could be big enough to let in wash down?

Out of curiosity can "windburn" occur during winter?

 

Scratch that foud this site http://www.gardenplansireland.com/forum/about416.html

Edited January 28, 2013 by AlvinD

[daltontrees]

You might pick up some extra ideas from the RHS site Conifers: brown patches / Royal Horticultural Society

[Scottie]

Have you thought of mites?

[Stephen Blair]

The salt will drip off your cars, if there's been snow then big clumps fall of the underside, or you salted your drive.

Do you wash your cars on the drive? Chemicals love trees!

[jonnygurkha]

I'm still a bit mystified by this one. The dieback extends to the top of the crown and any salt contamination would be very limited and only on the lower limbs if at all. No evidence of mites. I really need to brush up on my P and D knowledge. Thanks to everyone for their input.