Recent News

Sulfur shelves are one of the most noticeable fungi. The bright yellow to orange lobed fruiting body, composed of many overlapping shelves, may be up to a foot in diameter.

A well maintained lawn is an integral part of an attractive home landscape. Unfortunately, dandelion, plantain, and other perennial broadleaf weeds can become problems.

We have received several questions this summer about trees that are covered with a black substance on their leaves and twigs. It almost looks like the leaves have been dusted with soot, and the black dust can be rubbed off with a finger.

One of the largest insects in Iowa is the dobsonfly (Corydalus spp., Neuroptera: Corydalidae), an aquatic insect from rivers and streams that is frequently found in town.

Sap beetles are a common nuisance pest in late summer and fall. As the name implies they feed on plant sap, especially fermenting sap from ripe or overripe produce in the garden.

Although I've been diagnosing plant problems for a few years, I'm sometimes surprised at the number of plant samples we receive in the Clinic that have no infectious disease or insect problem (about half our samples).

The strawberry root weevil is a very common insect found throughout Iowa. The shiny black, hard-shelled adult weevils are about one-third inch long. They have a pear- or light bulb-shaped body and long elbowed antennae.

Tis the season and the adult beetles of the annual white grubs have emerged.

The increase in bagworm populations noticed on arborvitae, juniper, red cedar and other trees in southern and central Iowa over the past few years appears to be continuing.

Earwigs are outdoor insects that hide during the day in damp areas such as under mulch, dead leaves, logs, and piles of firewood, boards, stones and other debris or in rotted wood. They are active at night and wander in search of food and moisture.

Why do my ash tree leaves look so awful this spring? Some of the new leaves and shoots are falling off, some are misshapen, and the older leaves have large black or tan regions.

Several samples have come into the Plant Disease Clinic lately, showing symptoms and signs typical of Rhizosphaera needle cast.

They're back! This is the year the periodical cicadas (a.k.a., periodical "locust" and 17-year cicada) will reappear above ground in a small portion of east-central Iowa.

Several fungal needle diseases of conifers require fungicide sprays for satisfactory control. Fungicides do not cure needles already infected, but they protect the newest growth as it emerges.

We occasionally receive spruce samples in the Plant Disease Clinic that show yellowing of the needles, sometimes only older needles and sometimes both older and younger needles. Such symptoms are rarely a result of infectious disease.

The first step in diagnosing plant problems is identifying the plant and recognizing normal growth. Often, what looks "sick" may actually be the normal growth habit of a plant.