Catalpa tree rapid leaf drop

[ape]

Hello everyone,
This is my first question to the group so hopefully someone will be able to help me out. We have a client with a 80+ year old Northern Catalpa. The tree is experiencing rapid leaf drop on 2 large diameter(10") branches and wilted leaves on many others. The tree was pruned by a different company this spring before it leafed out, then bloomed beautifully. The temperatures have been up to 100 since the client has noticed this leaf drop and they have never watered the tree. There has been no new landscaping done or possible root damage. I asked how severely the tree was pruned and it was less that 30 % of the canopy. I took scrapings to inspect the cambium and it was green and healthy on the sick branches. There are 2 large, and very old wounds at the base of the tree which the tree has compartmentalized already, but I wonder if they could be the source of a fungal infection like verticulum(sp)wilt. I've been trying the city forester here in Ft. Collins, but no response, so I'd really appreciate the help if anyone can. I'll happily post some pictures if necessary. Thanks a lot. Tad

 

[treevet]

Yes, Pictures. And yes Catalpas do get Verticillium wilt, and Armillaria mellea may be of some suspect in conjunction with the basal wound.

Then again it may just be a normal tree response to drought. Start watering.

 

[Sunrise Guy]

Check the pH of the soil with a good meter/kit. Catalpas can fail in less than a month in the presence of a basic soil. With drought conditions and any nearby stone work that is getting hit by sprinklers with run-off towards the tree, you can see negative results in rapid order. I had a thirty foot Catalpa go stone dead in less than two weeks following the installation of a limestone walkway in its CRZ.

 

[treevet]

It is more likely just the dry weather complicated by the extreme heat. Tuliptrees are dropping leaves around here the last 2 days and are all over the roads as are many other trees.

 

[ape]

Thanks!

Wow, you guys are great, thanks so much for the speedy replies. Turns out, everyone got back to me today including the city forester who said it was probably due to the extremely cold spell last October(around 15F). He said it may be due to the cold snap itself, or that verticillium wilt came into play because of the snap. I cut into several of the affected branches looking for the telltale stain of a fungus, but all clear. I prescribed a heavy watering schedule(at least 1 inch per week) until September 1st when the frost threatens. Cheers and thanks for the help,
Tad