Q. Some of the lower leaves on my tomatoes have these spots on them. Is this a disease getting started?
A. This is probably not foliar disease. The foliar diseases on tomatoes would likely be larger or have yellowing occurring around those spots. The damage you see is typical of flea beetles, which are small beetles, some as small as their name implies. They can eat a hole all the way through a leaf, some of which you see here.
Flea beetles are typically worse in cool weather, which our spring has thus far been. They also tend to be worse on lower leaves and ones that are "softer." As the larger leaves develop, with full exposure to the sun, they may be less likely to be damaged, and as the heat sets in plants may just outgrow the consequence of the insect. However, if a lot of flea beetles starts attacking a small plant, they can stunt it. To keep that from happening, apply a broad-spectrum insecticide labeled for use on tomatoes that also kills flea beetles. The active ingredients of permethrin and acetamiprid are examples. Be sure to read the label carefully, follow all instructions and heed any warnings.
Q. I planted a long row of evergreens, and three right in the middle died. They did it before; we replanted, and now again. Will a soil test tell us anything? What else can we do?
A. Screening with a row of evergreen trees is a tempting thing to do. Unless space is limiting, I like to encourage folks to consider a different approach, such as a series of grouped plantings, and alternating between different plant species. Grouped planting may be of three or more, and not in a row, but in clusters. That way one can die and it won't look too odd. I had something like this happen to a row of four crabapples. One of the middle ones died after about three years. So I replanted, but it never caught up with the others, so it always looked odd, even with a healthy tree of the same type.
A soil test could be helpful if that spot had some soil issue due to construction debris, an old road, etc. Most evergreens prefer a soil that is more acidic. However, look for a local problem like a low spot, which could be causing a root rot. Now for the bad news - we have a saying: if a tree dies in a given spot, don't replant the same tree. Twice, and this is even more definite. For if the plant had a disease issue (like a root rot), then the disease organism is there.
It could be a case of transplant shock or adaptation to that location. With the wet spring of last year followed by the dry spell in the fall, we say some problems with evergreens show up through the fall and winter. The adaptation could be worse on poor soil, and a soil test would tell how to amend it. And maybe the third time would be the charm. A soil test would give guidance on whatever you might replace them with. To confirm why they died, one needs to submit a plant or a plant part to the diagnostic clinic, and the cost is $20.
Q. I have splitting occurring on the trunk of a small cherry tree. Is it normal? If not, should I do anything?
A. Trees will often get splitting at the base due to rapid growth. If the split is deep and/or very long, then it is NOT a healthy sign of vigorous growth. For large trees we'd start investigating lightning strike for a long split, but a small tree shouldn't attract lightning. Fluctuations in growth and temperatures aggravate the problem. Trunks are often damaged on the south to west side. If it is on other sides, then sunscald is not the problem.
Some trees are more prone to bark splitting than others. Cornell University has a fact sheet on bark splitting that discusses some other aggravating factors and mentions cherry as prone. They outline a procedure to help the tree heal. It is too long to include here, so either go directly to the publication (plantclinic.cornell.edu/factsheets/barksplitting.pdf), or contact us and we'll be happy to mail a copy.
The Central Missouri Master Gardeners are a volunteer group of 191 members, 122 of whom are Cole County residents, who maintain 11 beautification sites in Cole County, which are nonprofits or public entities. Master Gardeners must complete a basic training program of at least 30 hours of horticultural training, as well as 30 hours of volunteer service. The Missouri Master Gardener program is supported by the University of Missouri Extension.
Have a gardening question of your own? The Master Gardener Hotline is open from 12:30-4:30 p.m. Tuesday and Friday afternoons. Call 634-2824 or stop by the Cole County Extension Center at 2436 Tanner Bridge Road, or email your question to [email protected] for possible inclusion in a future "Ask a Master Gardener" column.