July 21, 1993

Water Gardens

Water is used in the landscape to create areas of calm and restfulness (though that certainly hasn't been the case throughout the midwest this year). Water features are not difficult to incorporate as long as important considerations are kept in mind. Two basic styles of water gardens exist, formal and informal. Formal pools have symmetric or geometric shapes and are appropriately used with neatly pruned shrubs and trees, in the middle of a large expanse of lawn, or as a focal point of a garden. The effect created is that of order and clear planning.

Mosquito Control Following the Floods of '93

When the flood waters recede from areas that have never been flooded before, there is likely to be pools and puddles of standing water left in places where we have never seen them. The abundance of standing water in stagnant puddles, pools and ditches will add to the flood cleanup misery by enormously increasing the number of mosquitoes from their already high population levels. Mosquito larvae that were in puddles and ditches before the flood have been flushed from the area. The next problem will come from new mosquito larvae that developed from eggs laid since the flood.

Plant Disease Clinic -- Highlights

Red Thread - Turf

Red thread on turf was diagnosed in the Plant Disease Clinic last week. The disease is caused by the fungus Laetisaria fuciformis and primarily affects perennial ryegrass, red fescue, and Kentucky bluegrass. The name of this disease describes the primary symptom very well. Red, thread-like structures (fungal mycelium) are visible on the tips of grass blades or leaf sheaths. The structures are described as "antlerlike" appendages.

Poor Fruiting Vegetable Crops

The cool, rainy weather this spring and summer has led to disease problems on trees, shrubs, flowers, vegetables, and turfgrass. The cool, wet weather has also affected fruiting of some vegetable crops.

Waterlogged Soils and Turf

The heavy rains this spring and summer have waterlogged many Iowa soils. Waterlogged soils limit soil aeration and will affect the growth and development of lawn grasses. The effects of waterlogged soils on turfgrass growth are a shallow root system, reduced leaf quality, reduced plant vigor, and increased disease activity.