Q. This bug, which I don’t recall ever seeing in my 30+ years of gardening in the northeastern San Fernando Valley, was all over my tomato plants this past summer. My questions are: What is it and what conditions caused it to appear in my yard? Is it likely to return this summer and, if so, are there any preventive measures I could take? How best to eradicate it if it does reappear?
This is a leaf-footed bug (Leptoglossus zonatus). They tend to show up on tomato plants and pomegranate trees. The adults are dark brown, about an inch long, with a narrow body and a light zig-zag stripe across the back. The back legs are noticeable in that they have an odd structure that looks like it has leaves attached (thus, the name). They have a long, pointy mouthpart that enables them to pierce leaves, stems, or fruit and suck the plant’s juices. Most of the time, the damage is minimal, but they can kill young seedlings and ruin immature fruit. Damage to medium-sized or mature fruit is usually limited to minor surface blemishes.
It likes to deposit its eggs either on stems or along the central leaf vein. The eggs are cylindrical, medium brown, and are arranged in a line so that they look like a string of tiny beads.
Most years, the population of these bugs is small enough to not be a problem. Mild winters, the presence of weeds (particularly weed seeds), and the availability of cover (such as wood piles) can cause the population to increase. To keep the population down, control weeds and move wood piles to a site away from the garden. Use row covers and hand-picking to decrease the damage. Insecticides are not very effective, so prevention is your best bet.
Q. About 40 years ago, I planted an ash tree (5 gallon) in my backyard. It grew into a beautiful tree and is now about 25 feet tall. Every winter it sheds its leaves. Last year I had some major plumbing done and they had to cut a couple of roots. This year it is barely shedding any leaves. Should I be concerned about the health of this wonderful tree?
When a tree experiences root damage, either from a mechanical injury or gopher predation, it will sometimes show its displeasure by sending up multiple root suckers. If the damage is severe, the tree may drop leaves and look generally unhappy (wilting leaves, halted growth, lots of suckers).
Since you know for sure that some of the roots were cut, your tree may just be pouting. Keep an eye out for more severe symptoms and take care to make sure it doesn’t experience any water stress this summer. Remove any suckers that may appear. If the tree is otherwise healthy it should grow back those roots in no time.
Los Angeles County
mglosangeleshelpline@ucdavis.edu; 626-586-1988; http://celosangeles.ucanr.edu/UC_Master_Gardener_Program/
Orange County
ucceocmghotline@ucanr.edu; http://mgorange.ucanr.edu/
Riverside County
anrmgriverside@ucanr.edu; https://ucanr.edu/sites/RiversideMG/
San Bernardino County
mgsanbern@ucanr.edu; 909-387-2182; http://mgsb.ucanr.edu
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