Cornmeal and Dry Molasses, Cicada Killers, Composting Plants, Long Legged Flies, Flower Beds Around
Q. I’m thinking about using cornmeal and dry molasses and also the corn gluten meal as a pre-emergent for crabgrass control next spring. What I can’t understand is why this stuff doesn’t get eaten up by various insects, birds, etc. Won’t it attract ants, flies, and other undesirable bugs? ’– D.A., Parker, TX
A. It will sometimes be eaten briefly if left dry on the surface of the soil, so it’s best to water in after applying. On the other hand, when broadcast it absorbs moisture from the air and goes to work right away. At this point it doesn’t attract the critters.
Q2. We recently moved to Parker and are enjoying the great variety of critters out here. There is a large burrowing insect with yellow stripes around a dark rear end that is one heck of an aerator in our flower beds. They dig pretty big holes and there will be a 4-6’” pile of dirt right next to it. They do not seem to be aggressive and you rarely see them go in or out of the holes. Should I be concerned about them? They are big and pretty fat ’– larger than your average wasp or mud dauber. ’– D.A., Parker, TX
A. The beast you have is the cicada killer. It’s a highly beneficial wasp. It sometimes acts aggressive but really isn’t. Only the females can sting but will only if you grab one and try to hold it ’– so don’t do that! Cicada killers parasitize cicadas, the loud summer singers, and take them back to the nests in the holes you have observed. The victims are fed to the young cicada killers. If you want more information on these fascinating insects, read The Texas Bug Book.
Q. I’m removing a euonymus with a scale problem. Should I trash or compost the fallen leaves? Is any special soil treatment necessary? ’–R.B., Dallas
A. No, compost the leaves and the entire plant. That is the best way to neutralize insects and diseases. Continue to use the Basic Organic Program and the soil will be fine.
Q. I have some large hanging blue fan flowers (Scaevola) plants on the patio. They are constantly being worked by something like a fly (in size and shape) except they have a bright green body. They look like they were painted metallic green. They are only a problem bothering my wife if she tries to sit on the patio. What are they and should be just ignore them? ’– J.W., Dallas
A. These are called long legged flies and are highly beneficial. The name comes from the fact that they have long legs. They are predators and eat insect pests including mosquitoes. They should be encouraged. See the Texas Bug Book for more details.
Q. I made a small flower bed around a tree and was wondering if it was going to hurt the tree. The tree is a live oak and is about 7 years old. I put a border about 6’” deep with dirt. ’– J.W., Dallas
A. Yes, trees being planted too low in the beginning is a problem. Likewise, soil being added later is a common cause of problems. Over watering should be added to that problem list. What the trees like best to have on the root system is shredded native mulch, not added soil and plantings that need frequent waterings.