Some mulched leaves can reduce dandelions

EAST LANSING, Mich., Sept. 9 (UPI) -- Michigan State University scientists say they've found pesticide-free mulched maple and oak leaves can reduce the number of dandelions on Kentucky bluegrass.

"The objectives of our research were to quantify the effectiveness of four maple and one oak species leaf mulch as an organic broadleaf weed control method in an established Kentucky bluegrass turfgrass stand, then to identify specific maple species that provide effective broadleaf weed control," said Alexander Kowalewski of the university's crop and soil sciences department and the study's lead author.

The scientists compared the effects of pesticide-free mulched maple and oak leaves on dandelion populations in an established Kentucky bluegrass lawn with applications made in the fall and data collected beginning in spring.

The researchers said their data showed common dandelion plant counts after one and two mulch applications at a high application rate showed up to 80 percent and 53 percent reductions, in that order.

Kowalewski said the results don't suggest mulched leaves can be used exclusively as an alternative to herbicides. But he said, "If home owners want to incorporate this practice into an annual maintenance program, the findings of this study suggest that an increased spring green-up and a reduction in common dandelion population could be observed."

The study appears in the journal HortTechnology.