Q: I found some poison ivy leaves that look very odd. They seem to be covered with pink warts. Kathi Worthy, Dallas
A: The warts are caused by gall making eryophid mites. These tiny creatures wound the leaf and insert eggs. Leaf tissue grows around them in these characteristic forms. I added a new word to my vocabulary recently: a cecidologist is one who studies galls on plants. The infestation doesn't hurt the leaves. I wish it did … the world might be a better place with a few less poison ivy plants!
Q: I want to use Drive XLR8 herbicide to control crabgrass. The label says I need a crop oil adjuvant. What is that? Ashley Frasca, Woodstock
A: An adjuvant is a chemical added to a pesticide to make it work better. Some gardeners add a drop of dish soap to their pesticide sprayer to cut water's surface tension and help the herbicide spread across waxy leaves. Methylated seed oil makes the chemical in Drive stay on the leaf surface longer, causing better weed kill. At this time of year, though, I don't think you need to kill crabgrass. The weed has already dropped thousands of seeds in your yard. Your best bet for crabgrass control is to apply a pre-emergent in March next year to prevent crabgrass seed germination.
Q: We have a cabin on the Cartecay River. It flooded last week. My hydrangeas, ferns, hostas, etc. are flattened from the floodwaters. Should I cut things back now or wait till later? Carol Binns, Ellijay
A: I'd use a hose to wash silt off everything and wait to see what happens. Many plants can tolerate occasional flooding. If your soil is quick to drain and dry, the plants may suffer no harm. I'd wait until next spring to do a final evaluation on their health. I have lots more information about recovering from flood damage inside and outside your home at bit.ly/GAflooding.
Q: We had a concrete wall repaired. There are now thousands of small concrete pieces in the nearby flower bed. Will the concrete leach into the soil and cause harm? Pam Covington, email
A: There might be a small rise the soil pH but it is probably nothing to worry about. Soil has a remarkable ability to buffer changes in pH. That's why it takes so much lime to negate the acidity of clay soil in your lawn. Remove as much of the concrete as you can but don't obsess over it.