Seasonal Differences in Growth Characteristics and Infiltration Rate in Kentucky Bluegrass Grown under USGA Soil System according to Establishing Maturity by Seeding Time

Kyoung-Nam Kim1,*   Chan-Ho  Cho2   

1Department of Environmental Design and Horticulture, College of Science and Technology, Sahmyook University, Seoul 01795, Korea
2Department of Environmental Horticulture, Graduate School, Sahmyook University, Seoul 01795, Korea


This study was conducted to investigate the effect of seasonal seeding time on growth characteristics and infiltration rate in Kentucky bluegrass (KB, Poa pratensis L.) according to establishment stage under USGA (United States Golf Association) soil system and to provide practically basic information on golf course design and construction. The USGA system was built with root zone layer (30 cm), intermediate layer (5 cm) and drainage layer (10 cm). Treatments were comprised of four seeding times (3/15, 4/15, 5/15, and 10/15) by season. Significant differences were observed with seeding times and establishing stage of maturity. Highest value in overall turfgrass density was 4.80 in April-seeding treatment, while lowest one 2.25 in October-seeding treatment. Greatest root growth was associated with plots seeded in May, being 28.2 cm in root length. But the plots seeded in October produced root length of 18.2 cm, being 35.2% lower than the May-seeding treatment. Response to thatch accumulation was slower than other characteristics of turfgrass density and root growth. The faster the seeding time, the higher the thatch accumulation. Infiltration rate, however, decreased with seeding time. Overall infiltration rate was greatest in October-seeded plots with 9,508 mm·hr-1, being 36.8 to 43.5% higher than plots seeded in March and April with 5,370 to 6,004 mm·hr-1. The longer the growth period (i.e., the faster the establishing maturity stage), the more vigorous the growth characteristics, but the lower the infiltration rate due to decreased percentage of macropore. In regards of turfgrass density, root growth, and thatch accumulation, proper seeding time is considered in April to May and in September in areas of middle Korea.

Figures & Tables

Fig. 1. Seasonal variation of the weekly mean air temperature in 2009 during the study. J through D in X-axis represents a month from January through December, respectively.