Plants and insects showing signs of the season
SALISBURY — With the cooler than normal temperatures and dryer weather, many are working to prepare lawns and cleaning spent vegetable gardens. Below are a few gardening questions I received earlier this week that may be of interest to those working in their lawns and gardens.
Question: There are Japanese hornets digging tunnels in our lawn. What can I do to control them?
Answer: These are not hornets but cicada-killers. They are giant hornet-like insects that are now actively digging in lawns. They are feeding on cicadas in nearby trees or wooded areas. The large wasp is generally harmless but can be a nuisance for those working in their lawns. These are generally considered beneficial insects as they control cicadas and other insects. There are insecticides that will control the insect. Go to http://granville.ces.ncsu.edu/2009/07/cicada-killer-wasps-now-active/ for more detailed information on the insect.
Question: I know that fall is the best time to renovate fescue lawns, but I have a lawn that is mostly Bermuda grass and I want to keep the grass as my lawn. How do I maintain a Bermuda grass lawn?
Answer: Bermuda grass is maintained much differently than cool season fescue. Bermuda is fertilized in the summer months and not in the fall. It goes dormant in cold weather and will survive very hot temperatures. Herbicides used to kill weeds in Bermuda grass will differ from those used on cool season grasses. Go to http://www.turffiles.ncsu.edu/articles/tf0016.aspx for more detailed information on Bermuda grass lawns.
Question: We found this huge caterpillar (insect was brought into the Extension office) on a tree limb in our yard. What is this caterpillar?
Answer: Hickory horned devil is the caterpillar of a regal moth. The ferocious-looking insect feeds on a number of deciduous trees including hickory, persimmon, sassafras, sourwood, sumac, sweetgum, sycamore and walnut. These are harmless to people with no real problem to trees. Go to http://www.ces.ncsu.edu/depts/ent/notes/O&T/trees/note108/note108.html for more detailed information about the insect.
Question: My late tomatoes are infested with tiny worms. They produce a tiny hole in the side of the fruit and inside the fruit is a very tiny grey worm. What are these and how do I control them.
Answer: These are tomato pinworms which are usually active in late summer and fall. The best control for the insect is to remove all spent tomato debris. Control with insecticides at this point is not practical. Go to http://ipm.ncsu.edu/AG295/html/tomato_pinworm.htm for more detailed information about pinworms.
Question: My maple leaves and other tree leaves have spots on them and are dropping leaves. What is causing this and what can I do to prevent this from happening next year?
Answer: Maples and other trees often get spots in the late summer and fall with no apparent disease problem; it’s a physiological disorder. However, with all the rain and excessive humidity, anthracnose is a rampant foliar disease on many species. At this point there is no practical control with fungicides. Removing fallen leaves and composting will remove spores that may reinfect next year.
Darrell Blackwelder is Rowan County Extension director, North Carolina Cooperative Extension. Call 704-216-8970.