Q. I just purchased a property and am going to be putting shade trees in between a building and the road. I am wanting a fast growing large shade tree. Suggestions for our area?
A: I consider selecting a tree too personal to do specific recommendations, unless one has reviewed options. We have a good publication that should make that easier. Please read through the publication, "Selecting Landscape Plants: Shade Trees," (extension.missouri.edu/p/G6800) and let me know if you have any questions.
Fall is an ideal time to plant trees, as they can develop roots through the winter. Weed growth around them is minimal, and moisture isn't generally an issue, unless they are evergreens. Nurseries often have fewer trees on hand, but some are willing to order if requested in time. We encourage a soil test to ensure you know if the soil requires any major nutrients or needs the pH adjusted. Locations adjacent to gravel roads may be alkaline, which is problematic for some trees, notably oaks.
Q. I have webbing with tiny specks inside that move around. It is on some outdoor landscape plants and I'd like to get rid of them with natural products.
A: This is almost assuredly spider mites that often come on strong in hot dry weather, which we are entering. To control them, you'll want to follow both the cultural controls and apply a spray, the easiest to find (and fairly effective) being insecticidal soap (top brand is Safer's).
Cultural controls: Providing plants with adequate water during dry conditions can minimize spider mite outbreaks. Periodic hosing of plants with forceful jets of water removes dust that collects on foliage and breaks up the webbing. Removing dust increases the ability of natural enemies to locate the spider mites. Directing the water toward the lower leaf surfaces helps to dislodge and kill mites. Do what you can to control weeds around the base and suppress dusty conditions, e.g. remove weeds and any debris and apply a layer of mulch.
Insecticidal soap must be applied to upper and lower leaf surfaces for effective control. Soaps are effective only when wet and should be used in the early morning or late in the day to delay drying and prevent leaf burn. Some plants are damaged by insecticidal soaps. Read and follow all label directions for safety and handling. If a plant is sensitive, then once the spray has dried, wash it off with fresh water. Insecticidal soap has little effect on most beneficial insects but will kill predator mites (the "good" ones).
Q. Are you having a Master Gardener class this fall?
A: We hope so. We're currently taking applications for a class to start on Aug. 28 and run for 13 weeks, from 6-9 p.m. Monday evenings. The cost is $150; give the extension center a call if interested.
Q: Are Japanese beetles winding down yet?
A: I hope so; please note the graph. In the past, the adults (beetles) seem to hatch out of the ground (from grubs) gradually and then pick up when the hot weather sets in, coming on strong around July 4. Once they start declining, it is often abrupt. However, in 2015, they hung around well into August.
Generally, they wind down by the end of July or early August. In 2016, after July 22, we only averaged 1,000 per day for a couple more weeks. Our peak catch in 2016 was a little more than 5,000 per day. They were substantially worse this year.