Washington, May 14 : Researchers have found the most effective seed mixture, as well as the right planting time needed for faster-growing and durable football fields.
Dr. John Stier, Associate Professor of Horticulture at University of Wisconsin-Madison in the US, led the two-year study.
His team noted that football fields are usually planted using slow-establishing Kentucky bluegrass seed mixed with a lower proportion of perennial ryegrass seed.
In their research, the team evaluated the effects of planting time and seed mix on three different blends of the two seeds.
They also studied each seed blend's ability to stand up to "football-type traffic".
"We were interested in determining the amount of time needed for athletic fields to establish before they could successfully support autumn sports," said Stier.
"We also wanted to see if the amount of time to establish the fields was affected by grass types and mixtures, and how planting time affected the relative proportions of different grass species that became established," he added.
During each year of the project, field plots were seeded three times: in late summer, as a dormant planting in late fall, and in the following spring.
Each plot was subjected to simulated football traffic from mid-August through mid-November of the year in which spring seeding occurred.
According to Stier, all planting dates provided acceptable turf quality by September, regardless of seed type.
However, Kentucky bluegrass-based mixtures planted during the summer provided better turf quality than mixtures planted in the spring. Dormant-seeded mixtures provided the poorest turf quality.
The team found that turf seeded with 100% perennial ryegrass was less sensitive to planting dates than Kentucky bluegrass turf. Summer and spring plantings provided similar quality and dormant seedings resulting in superior quality to Kentucky bluegrass-based dormant seedings.
Additionally, simulated traffic studies revealed that different levels of traffic did not affect turf species proportions.
The most consistently desirable results were obtained with a mixture containing 70%-80% Kentucky bluegrass and 30%-20% perennial ryegrass. The best results for mixtures dominated by Kentucky bluegrass came from fields seeded in late summer.
According to Stier, perennial ryegrass could be planted in spring and provided ideal ground cover with few weeds, but mixtures in which Kentucky bluegrass seed comprised 50% or more of the turf needed to be planted the preceding summer.
"The research outcomes can allow school systems to prepare better bids for construction and renovation of sports fields, making the fields more likely to meet expected performance standards and ultimately educe costs to the school districts," said Stier.