Metro-East Living

Weather to blame for leaves falling from trees

The leaves of a Pignut Hickory (Carya glabra) seem to have bladder gall mites.
The leaves of a Pignut Hickory (Carya glabra) seem to have bladder gall mites.

Q: We have a Japanese weeping cherry; the leaves are turning yellow and are falling to the ground. What can we do to prevent this?

S. B. of Shiloh

A: Your Japanese weeping cherry is just showing the results of a wet spring followed by a dry early summer. In the spring, the tree produced a large number of leaves due to the large amount of rain. Then as the summer became drier and drier, the tree’s roots could not absorb as much water to sustain the leaves and the leaves then dried up and turned yellow and then fell off the tree.

To help this stressed tree you need to give it a deep watering either by using a slow drip system over a longer period of time. Or you can use a deep root probe to apply water deeper into the soil. The second method is preferable as this method encourages the tree to send deeper roots and allows more water to be absorbed as the roots will have a greater depth to absorb water and keeps the roots from growing at the soil surface.

This problem is not just a problem with weeping cherry trees this year, but many other trees are losing many leaves which have also turned yellow. If someone researches a tree and it states the species is a ‘mesic’ species, this indicates that is prefers a moist condition to survive.

Q: I am growing three dozen tomato plants with six different varieties and two of these plants growing in different areas are showing some rather unusual coloration with bright yellow showing up on just the young developing leaves. I have used a rope wand to apply Round-up on weeds that are growing near the tomato plants and then later turned brown and dried up. Could the Round-up be causing this condition? If it is, what can I do?

K.T. of Caseyville

A: This could be the problem as once a plant is sprayed or touched by Round-up, the Round-up is carried to the young developing tissues at the ends of the stems and within a few days will turn brown depending upon the air temperature.

Magnesium deficiency could give very similar coloring of bright yellow with green veins remaining but usually all of your tomato plants’ young leaves would be showing this condition not just two plants.

Q: In a small wooded area behind my house is a tall growing young tree with these unwanted pests on the undersides of the leaf. Spraying is not an option because of its height. What can we do?

S. R. of Belleville

A: The leaves of a Pignut Hickory (Carya glabra) seem to have bladder gall mites. You do not have to worry about spraying or any control. Usually in July this mite will stop its activity and migrate back to the bark to spend the winter. There is usually not much damage done. If it bothers you next year, in early spring before the leaves bud out you can spray the lower branches with a dormant oil spray, which will suffocate them.

Charles Giedeman is a local contributing writer. Send your gardening questions to Lifestyle Department, Belleville News-Democrat, P.O. Box 427, 120 S. Illinois St., Belleville, IL 62222-0427, or email them to

Things to do this week:

  • Check how deep you have to dig into the soil before you find damp soil showing up; this will indicate how much strain is being put on your plants’ root systems.
  • If you do not want to use an insecticide to kill the Japanese beetles, you can spray them with lemon juice which will cause the beetles to leaves as citrus oils are irritating to them.