Problems with Elms

[PTI]

I've got a customer with 3 Allee Elms about 20 years old and 9-11" dbh. A lot of leaves are yellow with some spotting. They dropped about 25-30% of the leaves so far. The tips of most of the lower 2/3 of the tree have died back 3-4" also. Just got the soil test back and the pH is @ 7.0, with the base saturation @ 99%. Calcium is at 93%. Root zone is restricted with driveway and sidewalks and pretty compacted about 3-4" down.

The top 1/3 is pushing new growth.

Iron deficiency? Phloem Necrosis?

I was going to suggest application of Iron Sulfate, Vertical Mulching, and mycohorrizal inoculation. The CEC is 25.6%.

Should I wait until the pH drops before adding some low rate slow release fertilizer, or go ahead and put it down now?
How long should it take the pH to stabalize?

Any help is greatly appreciated.

 

[Urban Forester]

My guess is the CEC reading is not accurate unless they seperated out the calcium PRIOR to testing. With that level of calcium I would look to a test that would show ppm of soluble salts. Phloem Necrosis would've most likely manifested itself by now in a VERY visable way, so I doubt that's the problem. This appears to be a soil issue. I would try using Essentials 1-0-1 (Growth Products) an organic soil supplement. It has a carbon molecule that can HELP flush salt away from root systems and is also a food source for soil organisms.

 

[PTI]

Thanks. I pull some more samples and have them tested for soluble salts.

 

[treeseer]

how about posting a pic of the topmost roots?

bad compaction at 3-4" deep? vertical mulch, yesterday, assuming the root system is salvageable

 

[Ikeholt]

Have any lawn herbicides been applied? Any insects present? I have seen leafhoppers fry elm leaves in the past.