Why is my Desert Ash dying?

Rohdeo

I thought these trees were invicible, help my desert ash seems to be dying. For years I did nothing for my desert ash never watered it, feed it, pruned it, nothing but it always seemed to flourish.

Then about two years ago I noticed all the leaves on one branch would die. Later many new shoots would spring out from the seemingly dead branch with about 10cm of pale yellowy green leaves everywhere and over the course of the season they would die back again. Over several years this pattern seemed to spread to the entire tree. Now the shoots are coming out lower down the trunk and no more on the outer branches which appear to be completely dead.

Please note that so far we have done no pruning or removal of any dead limbs.

I need to mention that the tree has always had a yellow fungus/lichen on the bark of the branches as far as I can remember. Another desert ash nearby also has the yellow fungus/lichen but it seems to be doing much better although it too doesn't have nearly as much foliage as I would like.

Also several years ago we did disturb several root cords when we put in a pathway about two meters from the trunk. This pathway is made of pebble limestone that goes past the tree. Do desert ash mind alkaline soils?

Finally the tree has been getting alot more water in the last two years due to better maintenance of the lawn under and around the tree.

I hope somebody can help because it seems like the tree is fighting to survive but is losing and now its in its death throws!

I really like this tree, it used to provide alot of shade for the kids.

Cheers
Rohan

Rohdeo

Another thought, is it dying of old age

I was reading that these Desert Ash (also known as Arizona, Modesto, Fresno or Velvet Ash) have a life span of around 30 years.

My tree looks pretty old, it has a huge trunk diameter, maybe two foot and it is at least 30 foot high.

Is it time for the old girl to go?

Thanks in advance
Rohan

Rohdeo

Just to clarify........ my tree is a Narrow leafed Ash (Fraxinus angustifolia), we call it a desert ash here in my town in Australia. The town has many of this species as street trees.

Sorry for the incorrect naming above as a Arizona/Modesto/Velvet Ash (Fraxinus velutina).

Eric Frei

Pics would help, also considered a weed.

Weeds Australia - Weed Identification - Desert ash

Some facts here about it. Note toward the bottom this:-

Invasiveness Assessment - Desert Ash (Fraxinus angustifolia) in Victoria

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Rohdeo

Hi Ekka, here's some pictures for a better idea of what I'm talking about.

Cheers
Rohan

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Eric Frei

I recall seeing that orange stuff on trees in Adelaide when driving up the Gorge road, it likes darker moist places ... usually a creek nearby.

I haven't seen it up here and it's been 20 years since I left Adelaide.

I think it's a lichen and harmless to the tree.

Could be one of these... but I'm no lichen ID expert.

Xanthoria parietina - Wikipedia, the free encyclopedia

Mustard Powder lichen - Wikipedia, the free encyclopedia

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Garry Brockley

Like eric says it looks like a mustard powder lichen which is harmless to the tree it is very common in the uk too

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Rohdeo

Should what should I do? A severe pruning?

Eric Frei

I cant see that helping, might be time to replace it.

Have you done a soil pH test? You can get cheap kits from Bunnings even, like $20.

Make sure the soil pH is right, prune out dead wood and try this product to atleast the drip line.

Root extender

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