This is interesting info for warm season grasses. But where is there a study on cool season turf? Since soil temps must be elevated for organics to function in food delivery, a purely organic approach to management of C3 grasses does not seem practical.
For those concerned about EPA registrations, fertilizers do not require registration, And corn gluten meal (used as a preemergent) has been exempted from EPA regs. However, CGM is a root inhibitor, and may have the same negative effect on turfgrass roots that most chemical pre-ems have.
The use of natural enemies or parasitic organisms is not new. Been studied in this country for over 100 years. The problem with this approach is that the enemy or parasite must have a population of the pest to survive itself. And most things in nature do not ravage their life support like humans. So a natural control, using enemies or parasites, requires an acceptance of cyclical activity of the pest: as pest population builds, the predator organism population also grows, bringing the pest under control. But as the pest population is decreased, the predator population also decreases (food supply reduced), and the pest is allowed to prosper again. Using natural controls will never eliminate your pest - but then chemical controls never will either, LOL.
North central Indiana
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