It is not uncommon to also bring in some insects or spiders that were on the tree while it was growing outdoors. Fortunately, these “accidental invader” insect and spider pests are harmless.
Homeowners are reporting green or brown clusters hanging from the trees that look like a cocklebur. These clusters are caused by an eriophyid mite, and the damage is commonly called the ash staminate flower gall.
Scales are a unique appearing insect. Most of us learned insect basics in grade school and are looking for three body parts (head, thorax and abdomen) and six legs. Then someone tells us a scale is an insect and we look at it and it appears to be one smooth surface and there are certainly no legs in sight. It is at this point where most of us basically just take the entomologist's word for it that these things are indeed insects. It is primarily the females that we see on plants, and female scales are wingless and usually legless as adults. Scale insects start as eggs. The nymphs hatch and do have legs, and this is the stage referred to as crawlers that moves around and infests different parts of the plant. After that first stage that is mobile, all the rest of the stages do not move.
Spruces are a favorite evergreen for yards and windbreaks in Iowa. However, they are susceptible to a few problems that can leave them unsightly. Knowing about these common spruce ailments is the first step toward minimizing problems with these beautiful trees.
Many gardeners strive to grow beautiful, insect-free plants, but as an insect lover, my favorite plants are the ones that always get pest insects. One favorite in my yard is a yellow daisy that becomes infested annually with beautiful red-colored aphids. For good insect viewing it is hard to beat the aphids. Aphids come in a variety of sizes and colors but most have a soft, pear-shaped body up to one-eighth inch long. Common aphid species come in all shades of green as well as black, pink, yellow and the already-mentioned bright red. The one distinguishing characteristic present on all aphids is not always easy to see, but it is there: each aphid has a pair of tubes on the top side of the back end of the abdomen. The tubes are called cornicles and are used to secrete wax and other substances.
There are both wingless and winged forms, according to Matt O’Neal, assistant professor, Entomology. He says wingless soybean aphid adults are about 1⁄16 inch in length, pale yellow or green, and have dark-tipped cornicles (tail pipes) near the end of the abdomen. The winged form has a shiny black head and thorax with a dark green abdomen and black cornicles.
When (and if) Iowans think about centipedes they probably picture the house centipede. This common home and garden resident is up to 1.5 inches long and has 15 pairs of very long, slender legs stretched proudly to the sides of the body. Each of the 30, fragile-looking legs is almost equal to the length of the body and is encircled by dark and white bands. The body is brown to grayish-yellow with three dark stripes.
Silverfish and firebrats are about a half-inch long, wingless, flat insects with two long, slender antennae on the front and three long, slender "bristles" at the rear of a tapered, carrot-shaped body. As a kid those three bristles held at right angles always seemed to add to my presumption that there were perhaps an alien listening device and not insects at all. Most silverfish and firebrats are covered with scales (similar to those on butterfly wings) that have a silvery sheen in the case of silverfish.
This week's column destroys some myths on how bugs enter your bathroom.
One of the fascinating features is the incredible diversity of insects that can feed on one kind of plant. Our understandable obsession with a few serious insect pests on a relatively small number of crop plants skews our view of the insect/plant relationships around us.