June 15, 2001

Sycamore Anthracnose


Leaves have been falling from sycamore trees. This early loss of leaves can be alarming. A close look at the fallen leaves will reveal brown areas that typically follow along the veins of the leaves. These areas of browning are often V-shaped.

Anthracnose tends to be most severe when extended cool and wet weather occurs in the spring. The fungus that causes sycamore anthracnose needs wetness in order to infect the leaf tissue. Leaves are most vulnerable to this fungus during the first weeks of growth.

Variegated Cutworm - The Outbreak That Was


Hosta growers, vegetable gardeners and others had a tougher time than usual this spring with one of our less common pests, the variegated cutworm . The variegated cutworm is found in sites as varied as alfalfa fields to home gardens. A nickname for this species is "climbing" cutworm because of its habit of climbing plants at night to feed on foliage, flowers, buds and fruits. Variegated cutworms do not damage plants by clipping at ground level as is usually typical of cutworms.

Dividing Bearded Irises


Bearded irises are one of the most popular and widely grown perennials in the home landscape. The colorful, orchid-like flowers of bearded irises are composed of 6 segments. The 3 inner segments (petals), which are generally upright, are referred to as standards. The drooping, outer 3 segments are known as falls. The common name comes from the fuzzy growth or "beard" which runs down the center of each fall. Bearded irises are available in a wide range of colors, including white, yellow, orange, pink, wine-red, blue, and purple.

Next up in the Hosta Garden: Slugs


Slugs are an occasional problem for most Iowa gardeners. Hosta growers, on the other hand, seem to always have more than their share of slugs. During drought years slugs almost disappear from sight. Prolonged periods of wet weather, however, have the opposite affect and numbers become noticeable.

Slugs are close relatives of snails, clams and oysters. Slugs have soft, unsegmented bodies and look very similar to snails but without the external shell. When stretched out the average Iowa garden slug will be up to 1 inch in length.