Neil Sperry's Mailbag

DEAR NEIL: I have a beautiful 9-year-old red oak tree that has been afflicted by some type of fungus. For three years it has put out new leaves in the spring, but they remained stunted and pale green in color with dark green veins. By late summer they turn brown and fall off. This autumn I've had other new leaves similar to the spring. Other red oaks nearby look great. This is in white, chalky soil.

Your tree is suffering horrible iron deficiency. You have listed the textbook symptoms. It is usually caused by our planting a red oak that is not a true Shumard red oak into alkaline soil. Pin oaks look almost identical to Shumard red oaks and will not survive alkaline conditions for more than 6 to 10 years. Adding iron in that situation will be of no help since the problem will only get worse. The only other possible cause (and also the one that might hold in areas with acidic soils) would be severe trunk damage that now limits the flow of nutrients to the leaves. That could have resulted from sunscald or borers after the tree was planted. In both cases it sounds like it's time to replace this tree. Talk to your nurseryman for a second opinion.


DEAR NEIL: What is the best time to dig and divide banana clumps? I tried it in October one year and they died.

Try very late winter, just before the new growth starts for the spring. Use a sharpshooter spade to cut through the masses of roots.


DEAR NEIL: I saw your answer about spraying pecans and fruit trees. I tried Googling it as you described and I didn't get anywhere. Do you have other suggestions?

I did both Yahoo and Google searches and found a variety of links. However, a few of them are outdated and should be taken down. The best way to get the most current information is to go to the Texas Cooperative Extension's online bookstore and click through to whatever topic you wish. In your case, you're looking for bulletin E-145. The site is http://tcebookstore.org>.


DEAR NEIL: What would cause ugly growths on the lower branches of an oak tree? They look like corky masses with worm holes in them. Will they hurt the tree?

Those sound like insect galls. Each species of oak has its own inherent types of galls. The adult insect flies by and stings the twigs and branches. She lays her eggs in the process, and the gall you see is the plant's reaction to the sting. There is nothing you can do to control them galls. The good news is that they, on their own, do nothing


Have a question you'd like Neil to consider? Mail it to him in care of this newspaper or e-mail him at mailbag@sperrygardens.com. Neil regrets that he cannot reply to questions individually.

Neil Sperry
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