Dear Neil: What product can I use to eliminate bermuda mites? How do I apply it?
A: Google “university bermuda mites” and see what you turn up from the Land Grant University (ag college) websites. They will all tell you similar stories. Bermuda mites are almost impossible to stop by spraying. Bifenthrin may help when applied with a surfactant, according to one Texas A&M entomologist I spoke with, but the more important part, he and others add, is to mow low (1 inch or less), bag the clippings from all affected areas and discard them off site, and mow frequently to avoid letting the grass grow too tall. They suggest dethatching in spring to remove compacted grass that might be home to the microscopic, stunt-causing mites. And if you do spray, be sure your spray is directed down into the leaf sheaths.
Dear Neil: What is this weed, and how can I get rid of it? It is taking over my lawn.
A: Wild violet. I get this question every couple of years. I answer it honestly, and then I get complaints from those who think it’s beautiful and that I’m harming a Texas wildflower. So, preemptively, I offer this comment: if you have a plant that you don’t want in your lawn, you have the right to try to eliminate it. Or, if you prefer, you can dig and relocate it to an area where it can be featured. To your answer. Obviously, it’s not a grass. That means that a broadleafed weedkiller will eliminate it, but experience warns me to tell you that it’s one of the more difficult weeds to eliminate. Those funnel-shaped leaves conduct the weedkiller spray droplets down and off the leaf surfaces. To avoid that, include one drop of liquid dishwashing detergent per gallon of spray. Use a fairly small droplet size when you spray so that you can coat the leaves uniformly. Repeat, if needed, on 15-day intervals until you eliminate it.
Dear Neil: I saw your story about take all root rot and the product that would stop its spread. The disease only seems to be showing up on the St. Augustine I have in the shade, and that product Disease EX didn’t help. What else can I try?
A: You’re misidentifying the cause of your problem. Take all root rot shows up in all kinds of lighting: sun and shade alike. Failure of St. Augustine to grow in shaded areas is the most common question I get out of all the thousands of questions I’m asked. St. Augustine requires a minimum of 6 or 8 hours of direct sunlight daily during the growing season to thrive, which is why all sod farms are in full sunlight. Many people have the mistaken idea that it must have shade. The acid test is to look at the thinning area. If the grass gets thinner the farther you go in toward the trunk of the tree, then the issue is the shade, not a disease. You either need to remove a tree or two (probably not a good plan in Texas) or switch over to a shade-tolerant groundcover.
Dear Neil: We have a Desirable pecan on property in Brewster County (10 miles south of Alpine and about 600 feet higher in elevation). We lost about half of its top growth two winters ago, but there is new growth being produced. I assume we should trim out the dead growth at this point. Is that correct?
A: Yes. The photo that you attached shows that new growth to be very vigorous. Trim out the new growth in a way that will leave no dead stubs. That dieback was probably just due to unusually vigorous late-season growth that hadn’t become fully hardened and ready for winter. You should be fine.
Dear Neil: I have a mature hickory tree that had an unusual growth resembling a horse’s hoof on its trunk. Actually there were several. I removed them, and now gray growths are emerging. What are these, and what should I be doing?
A: You may very well have fungal conks. Those are growths that develop from disease infections deep within the wood of the tree. They’re not something a home gardener can address. You need to hire a certified arborist to look at your tree soon. It may not be possible to save the tree if the infection has spread within the trunk. It may have to do with the age of the tree. Older trees become more susceptible to this sort of problem.
Dear Neil: Once again I am losing the battle with my cannas. Something is devouring them at night. I followed your advice of cutting the foliage down in the fall and removing and burning it. I sprayed with garden-safe spray this spring, but I still have the webworms. What can I do?
A: That’s right on trimming off the browned foliage after it freezes. You can shred it or send it to the landfill. Burning is subject to local regulations. But these are canna leafrollers, and you’re going to have to use a systemic insecticide such as Imidacloprid several weeks prior to when you typically first see their damage. That obviously would be before this time next year.
If you’d like Neil Sperry’s help with a plant question, drop him a note in care of The Eagle, P.O. Box 3000, Bryan, Texas 77805. Or email him at firstname.lastname@example.org.