Weeping Willow Tree
Black spots and yellow leaves

Q: We recently planted a decent size willow tree and noticed that there were black spots in places on the trunk, and some of the branches are black at the tips.

Now the leaves are turning yellow and almost look like they are shriveling up. Please help us. Do you know what the problem is?

We live in Santa Fe NM, and the tree came from Santa Rosa about 1 hour away. It was planted 1 week ago and was dug up 3 days prior to planting.

Thank You, Kelly

A: I will assume that the root ball size was adequate for the tree. A root ball that is too small will not bring enough roots to sustain the tree during the critical initial transplant shock period.

A rough rule of thumb is at least 10" of root ball for every inch of trunk caliper (diameter) measured about 6" about grade, i.e., a 3" caliper tree should have a bare minimum 30" diameter root ball. Bigger is usually better as it gathers more root system for the tree, which helps it re-establish better in its new home.

This being said and assumed, it sounds like the tree may have been "burned" during transport to your house. If the crown (the branches with the foliage) was not covered or protected somehow while the tree was being transported, the wind may have dried the leaves out, leading to shrivelled leaves. Even driving just 20 miles per hour for the one-hour trip would be sufficient to dry the leaves out very badly.

If this is what happened, all you can do is water the tree once a week in the absence of adequate rainfall, and wait to see if the tree pushes out replacement foliage from its energy reserves. If it does, continue a proper watering program when needed, and wait till fall to do any fertilization.