In Indiana, Purdue University researchers and the USDA Agricultural Research Service found that a fungus called Metarhizium brunneum, does a great job of killing the pesky “white grubs” that eat turf grass roots on lawns and especially golf courses. The white grubs eat the roots of the grass turning it brown or even turning spots completely barren.
The researchers’ solution is a bio-based clay granule consisting of fungus created through “liquid culture fermentation” that, depending on the rates applied, killed about 50% to 70% of the grubs within 7 to 10 days. While a chemical based insecticide killed them faster and killed about 95% of the grubs, they found the long-term application didn’t fare as well. The bio-based fungus application was able to kill more of the larger grubs in the fall than the insecticide, which didn’t seem to work as well with the cooler temperatures. The fungus based application also differs from regular insecticide in that it only targets white grubs and other insect turf eaters and does not harm other wildlife, animals or humans.