The leaf drop is probably due to anthracnose. Anthracnose is a common fungal disease of trees in Iowa. Anthracnose may occur on ash, sycamore, maple, oak, walnut, and other deciduous trees (see encyclopedia article Anthracnose on shade trees). Cool, rainy weather in spring favors anthracnose development. Symptoms of anthracnose vary with the tree species. Anthracnose is a fungal disease that causes spots to develop on the leaves, especially the lower ones, of ash, maple, oak, black walnut and sycamore.
Fortunately healthy trees can survive occasional attacks from this disease. Rake and destroy fallen leaves. Make sure the trees receive a thorough watering during extended dry periods. Plant bugs are small green insects that suck plant juices. Their feeding. If leaves are falling off your green ash, and you notice the other symptoms discussed, your tree is probably infected with verticillium wilt.
Ash Anthracnose Ash. Sep 01, Anthracnose, a tree fungus, can cause ash trees to lose their leaves early. Moist, humid weather allows the fungus to thrive and turns leaves a blotchy brown. Anthracnose tends to not be a huge issue for ash trees. Raking and destroying diseased leaves can help minimize the harm. May 17, A disease that’s causing ash trees to lose their leaves won’t kill the trees. Many people have noticed leaves falling from their ash trees and are worried the trees are dying.
They can stop worrying, according to Joe Zeleznik, North Dakota State University Extension Service forestry specialist. “The leaves are falling due to a fungal problem called ash anthracnose” Zeleznik says. Jun 07, Location. new york. Jun 2, #1. Help!! One of my ash trees is dropping it's new leaves. The leaves are green and they're dropping like crazy. I don't remember this ever happening other years and I don't want to lose the tree. It's in the front yard and shades the house beautifully.
It is caused by the rust fungus called Puccinia sparganioides, that mostly infects white and green ash trees. The symptoms of ash rust appear in mid-May. You may notice yellowish-orange spots on the surface of the leaves. The leaves that are infected wilt and eventually die. It is a minor, but noticeable disease. Repeated rust infections may weaken the trees, leading to winter damage and dieback.
Mar 27, Being the tree is in a small cutout area, the 18 square feet of exposed soil may not be providing enough water to hold leaves when temperatures rise.
Another possibility could be spider mites, but they usually cause yellowing of the foliage before dropping. It may also be in an area of soil that either drains especially well or especially badly, compared to the other trees, so is getting less or more water than they are.
Neither of these sound too likely, since you say whole branches aren't leafing out.