Milky spore is used for control of Japanese beetle grub. Results from use of milky spore have been uneven, although recent advances in the production of this product may improve consistency of results. It is essential to follow instructions carefully.

Another disease organism that is being developed for use in turfgrass is the bacteria Bacillus thuringiensis. This bacterium has been used in agricultural crops for several years. It is a disease that attacks various caterpillars, and new strains are being developed to work more effectively against the caterpillars found in turf. This product is relatively slow acting, but it is safe to humans and the environment.

During the past two or three years, increased work on parasitic nematodes that attack various turf pests such as mole crickets, white grubs, and caterpillars has resulted in some commercial releases. Results of their use are variable, but once released, they continue to work for years. However, like many beneficial organisms, there must be a steady, low level of the prey insect present for them to survive.

Another area that shows some promise is the use of endophyte fungus carrying grasses for insect resistance. The presence of this endophyte fungus in some turfgrasses produces various compounds that provide some resistance to insects. Laboratory studies have shown some outstanding resistance to insects for several species of fescue and ryegrass. However, some field studies have shown less than spectacular results. Much work is continuing in this area, and the future will most certainly see increased resistance in turfgrasses. The varieties available on the market now should be viewed with caution. Although they may help reduce some insect problems, they will not eliminate them.

There are also a number of organic or biological materials on the market. Crustacean and clam shell particles, diatomaceous earth, insecticidal soaps and other substances have some logic behind their use. Many act as an irritant and break down the insect's cuticle, others interfere with the insect's ability to regulate its body fluids and so on. Each has its own particular mode of action. Testing of these materials on turf has been fairly limited, but some studies have shown some positive effects.

While the benefits of organic pest control are many and more effective controls are likely to be available in the future, in general, the organic approach is slower and less effective and, as a result, more damage may result. In areas of high turf management where top quality turf is expected, it may be difficult to accomplish with a strictly organic or biological approach.

Changes in turf management will result in changes in the insect fauna in general in ways that cannot always be anticipated. For example, green June beetle adults lay more eggs in areas that contain animal manure. The use of organic fertilizers has also been shown to contribute to green June beetle problems in turf.

At the same time, research is underway to improve application techniques for currently used pesticides to render them more effective and reduce environmental risk. Such is evident in some of the new equipment available on the market such as high-pressure injectors. These units improve performance by forcing the insecticide into the soil, leaving virtually no surface residue.

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