Insects now the problem for plants
Last week it was about diseases — and it's still about diseases because of the cool, damp weather.
Keep an eye on your tomatoes for early blight and other tomato diseases. Remember, just because you don't see any symptoms on the leaves doesn't meant the leaf isn't infected. Infection occurs before the symptoms show up.
If you are going to use sprays for preventing diseases, follow label instructions for how often and when you can harvest the crop.
I have been so focused on watching for diseases that a few insect problems have cropped up in my landscape. They do that!
While weed eating around my shrubs, I found dogwood sawfly on my variegated redtwigged dogwood. These sawflies can completely defoliate dogwoods if populations are high.
On the variegated dogwood, I would have walked right by them. On the green leaf dogwood, it was easy to spot. They feed on all species of dogwoods, including trees.
Sawflies have chewing mouth parts; therefore, they defoliate the plant by eating the leaves. Even a small population can strip the foliage, leaving the midvein of the leaf.
When they first hatch, you really must be looking to find them. Since they are midseason pests, they hatched about a week or two ago in central Ohio.
They are typically found on the underside of the leaf surface though they can be found on the top. When they rest, they curl into a circle.
As they grow, the final instar is around one inch and are covered with a white flocculant-like coating. When they curl up, they look like bird droppings.
Even if you can't see them, you will see holes in the leaves in the early stages and then the entire leaf is chewed and the foliage missing.
These can be knocked off into a bucket of soapy water if populations aren't out of control. If populations are high, you can use pesticide sprays that are labeled for sawflies on ornamentals.
Keep in mind, these are NOT caterpillars and bacillus thuringiensis will not kill them. They are sawflies and are the larval stage of a wasp-like species. Use a pesticide containing pyrethroids (bifenthrin, permethrin, etc.).
The sunflower head-clipping weevil damage is apparent in coneflower plantings. If you see the droopy heads of the coneflowers, pick them off and dispose of them. Pesticides aren't effective on them.
What are you seeing in terms of Japanese beetle populations around the Miami Valley? I am not seeing very high populations at all in my landscape. Email me and let me know what you are seeing — bennett.27@osu.edu
Finally, a quick update on the China seeds issue. The Ohio Department of Agriculture would like to collect the seeds that you received from China. You can mail them to ODA at this address: The Ohio Department of Agriculture, Attn: USDA-SITC, 8995 E. Main St., Building 23, Reynoldsburg, OH, 43068.
You can also drop them off at your local Ohio State University Extension office. If you plan on doing this, please check their website for their current office hours. Not all offices around the state are open all day every day. Information for drop-off will be on their website.
Pamela Corle-Bennett is the state master gardener volunteer coordinator and horticulture educator for Ohio State University Extension. Contact her by email at bennett.27@osu.edu.