July 19, 1996

What Makes an "All-American" (Flower or Vegetable)?

With the United States hosting the 1996 Summer Olympic Games and the media and sports world filled with talk about "All-Americans" and "Olympic medal hopefuls", I thought now would be a good time to talk about the All Americans in the horticulture, rather than sports, world.

Cherry Leaf Spot

Cherry leaf spot, sometimes referred to as "shot-hole", is caused by the fungus Coccomyces hiemalis. The disease first appears on the upper side of the leaf as small, circular, purple spots. Later, the spots turn brown and form a definite boundary. After the cherry leaves become infected, they turn yellow and fall. Only a few lesions per leaf can result in leaf yellowing and defoliation. Although the disease occurs primarily on the leaves, fruit, stems, and leaf petioles may become infected when the disease is severe.

Dutch Elm Disease

Many elm samples have been submitted to the Plant Disease Clinic in the last few weeks that have tested positive for Dutch elm disease.

Dutch elm disease affects all elm species. Dutch elm disease is caused by the fungus Ophiostoma ulmi, which invades the water-conducting vessels of elms. The leaves of trees wilt, turn yellow or brown, and then fall. Another diagnostic feature is the formation of brown or green streaks in the infected sapwood. This discoloration is visible when the bark is peeled back on symptomatic branches.

Grease Ants

The name grease ant is commonly used for one of the smallest ants found in homes in Iowa. These ants are technically known as thief ants. They are very small; only l to l mm (1/6th inch)long. They are smooth and shiny and may be yellow to light or dark brown. Indoors, these ants nest in cracks and crevices of walls and cabinets, under floors and behind baseboards. The nests are frequently difficult to locate since the ants travel great distances in search of food. Though they will eat almost anything, these ants prefer to eat grease, fats and meats.

Irrigation Equipment

A wide range of watering equipment is available to home gardeners, ranging from a simple watering can to an automatic, underground irrigation system. A common watering tool for gardens and lawns is the portable sprinkler. There are several different types of sprinklers, each producing a characteristic spray pattern. Portable sprinklers are inexpensive and readily available. When used properly, they do a good job of watering. The most commonly used portable sprinkler is the oscillating sprinkler. An oscillating sprinkler consists of a horizontal tube which has several outlets along it.

Lawn Irrigation

Just a few short weeks ago we were wondering when the rains were going to stop. Currently in central Iowa, many lawns are dormant because of lack of rain. Homeowners have two options for lawn care when it comes to hot, dry weather. One is to simply allow the turf to go dormant. The other alternative is to properly water the lawn to maintain green turf throughout the dry spell.