Q: There is a white, powdery film on my sago palm fronds. Is it cycad scale? If so, what do I do to remove it? K.E., League City
A: It sounds more like powdery mildew. Whether the issue is insects or disease, I would spray Garrett Juice augmented with 2 ounces of orange oil and 1 tablespoon of Bio Wash per gallon of Garrett Juice.
Q: I can't grow much of anything under 40- to 50-foot bur oaks. Two-thirds of the yard is extremely rocky, the other is sandy. I was thinking about replacing the existing dirt, weeds and grass with buffalo grass. What soil amendments should be put down? Will buffalo grass grow under trees? C.S., Double Oak
A: Buffalo grass needs no amendments or extensive bed preparation, but it will not grow in the shade of trees. You should consider shade-loving ground covers or native shredded mulches.
Q: I live in East Dallas and I had a large tree removed in May and had the stump ground out. The St. Augustine grass is turning yellow in a circle about 15 feet diameter where the tree was removed. The rest of the lawn is very green and healthy. Can you suggest something I can do to make it look like the rest of the lawn? P.M., Dallas
A: Right now is the best time of the year to apply a half inch of compost on the problem area, and that's the best solution. If some of the grass is completely dead, replace the grass first, then apply the compost.
Q: My fruitless mulberry has crotches where the limbs meet the trunk that hold water and debris. Should I try to fill them with something? J.M., Plano
A: Filling cavities with any material does no good and can even create rot and other problems.
Q: We have an automatic mosquito system installed in our yard. Is there anything more environmentally friendly than permethrin that we could use? S.G., Kingwood
A: There is the essential-oil product called Essentria and a new product called Safety Net Mosquito Defense from Mosquito Steve, bottled in Dallas. All the other choices are either too toxic or do not work.