Good day. I have an Ash tree (not sure of it's a White or Green Ash) in my front lawn, approx 45 ~ 50 feet in height. It currently has beautiful green leaves. For the past two weeks, however, it has been losing its leaves faster than in the fall. Sometimes it looks like it's snowing. Fallen leaves do not show any signs of disease or bugs. FYI, I live in Montreal, Quebec, Canada. Weather is now in the 60F to 75F range with normal levels of precip. Can you shed any light on this matter. Thanks for your help in advance. Mike.

Reply to post by Mike Schwar, on May 31, 2003 at 19:09:21:

Look at the site linked below. Near the bottom of the page is a section on damaging agents for Green Ash. Although I am in California, USA, and do not have direct experience with your tree, I would suspect anthracnose to be involved.
We had a very heavy defoliation of Ash species and Platanus species, due to anthracnose, following a rainy Spring this year.
You can also look up White Ash (and other trees) at the Silvics site. That species seems to have air pollution sensitivity, among other problems.
Whatever the problem, a generally good approach is to make sure to support the tree with good irrigation, etc. Diseases caused by organisms are only some of the stress factors affecting trees.

Reply to post by Mike Schwar, on May 31, 2003 at 19:09:21:

If the leaves are beautiful green, falling off, and there is no sign of disease or bugs as you say, I would look for a barely visible insect that is eating away at the abcission layer or another part of the petiole. If you find such a creature let me know. It is possible that you will need a hand lens or a strong magnifying glass.