Case No. 1: Restoring natural balance Biologically rich soils help suppress turf diseases. This was well illustrated a few years ago when specialists at Michigan State University began evaluating a biologically enriched lawn fertilizer.
The product was found to promote a healthy turf and to steadily do away with thatch buildup (the principal aim behind the product's formulation).
But in addition - and this was totally unexpected - the fertilizer also reduced and eventually eliminated other commonplace lawn problems such as dollar spot, fusarium, yellow patch, and others.
Further testing confirmed the initial observations and showed that the lawn diseases were not so much destroyed as overwhelmed. By introducing beneficial bacteria along with slow-release natural plant foods into the lawn, the hostile microorganisms were no longer a dominating presence.
In simple terms: Once the natural balance was restored, the turf problems declined and ultimately disappeared.
Case No. 2: Thatch problem
Several years ago I was taken to a suburban section of Minneapolis and shown two lawns side by side facing the same direction and with identical slopes to the street.
The one lawn had a heavy thatch problem and had to be watered three times a week in dry weather.
The second lawn had been in a similar situation, but after being treated for two years with a biologically active organic fertilizer, the lawn needed to be watered only in prolonged dry spells. For the most part the natural rainfall was sufficient.
The reason for the different watering schedules became obvious when core samples were taken from both lawns. Though it had rained heavily the night before, only the top 2 or 2 inches of cores from the thatch-infested lawn were moist.
In contrast, cores from the treated lawn were uniformly moist to the full depth (more than six inches) of the core sample, indicating a much more natural and healthy soil. Both lawns appeared pleasantly green, but the less natural one required far more upkeep.