MADISON, Wis., May 14 (UPI) -- A U.S. team of scientists says it has found the most effective seed mixture and planting times for producing faster-growing, more durable football fields.

University of Wisconsin researchers said their findings can help schools and contractors pare the usual 9- to 12-month waiting period between planting new fields and opening the fields to autumn football traffic.

Associate Professor John Stier led the 2-year study of seed mixtures and planting times. He noted football fields are usually planted using slow-establishing Kentucky bluegrass seed mixed with a lower proportion of perennial ryegrass seed. The objective of his study, said Stier, was to evaluate the effects of planting time and seed mix on three different blends of the two seeds.

The researchers found, among other things, all planting dates provided acceptable turf quality by September, regardless of seed type. However, the study concluded Kentucky bluegrass-based mixtures planted during the summer provided better turf quality than mixtures planted during the spring.

Dormant-seeded mixtures provided the poorest turf quality and turf seeded with 100 percent perennial ryegrass was less sensitive to planting dates than Kentucky bluegrass turf.

The research is reported in the journal HortScience.