Root Distribution of Creeping Bentgrass and Annual Bluegrass on Golf Course Putting Greens
Open Access
- Author:
- Lyons, Eric Michael
- Graduate Program:
- Plant Physiology
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- October 13, 2003
- Committee Members:
- David Robert Huff, Committee Chair/Co-Chair
Daniel Paul Knievel, Committee Chair/Co-Chair
David Eissenstat, Committee Member
Peter Landschoot, Committee Member
Jonathan Paul Lynch, Committee Member - Keywords:
- creeping bentgrass
annual bluegrass
turfgrass
Root distribution
nitrogen
phosphorus - Abstract:
- Three experimental cultivars of annual bluegrass and two cultivars of creeping bentgrass, ‘Penncross’ and ‘Penn A-4’, were planted on an experimental golf green at Penn State University. Two different nitrogen rates (approximately 130 kg N ha-1 year –1 and 390 kg N ha-1 year –1) were applied and tiller densities and root mass distributed at different depths were measured. The creeping bentgrass cultivars had more root mass (0-3cm) than the annual bluegrass cultivars throughout the length of the experiment. In the two deeper soil fractions (3-12cm, Below 12cm) creeping bentgrass had greater than 4 times the total root mass than annual bluegrass. In both years, there was over a 25% decrease in the amount of roots present at all depths for both species from the June harvest dates. Penn A-4 had greater root mass than Penncross below 12cm of depth and also had greater tiller densities than Penncross throughout the experiment. Annual bluegrass cultivars had greater tiller densities than creeping bentgrass. In 2001, the creeping bentgrass cultivars showed increased root mass below 12cm with the low nitrogen rate. The annual bluegrass showed no change in root mass in response to nitrogen rates. In 2002, creeping bentgrass showed no response to nitrogen rate while the annual bluegrass showed increased root mass in the top 3cm with the high nitrogen rate. Tiller densities increased with the high nitrogen rates in both species. Annual bluegrass increased its specific root length in response to the low nitrogen rate while creeping bentgrass remain unchanged. The effects of spatial phosphorus supply and the use of a novel phopshorus fertilizers were also explored and discussed. In all three spatial phosphorus supply experiments, creeping bentgrass exhibited increased root mass in the areas of the root zone where phosphorus was present compared to the areas where phosphorus was absent. The role of nutrient availablity in the competition between annual bluegrass and creeping bentgrass is discussed. The idea of space as a limiting resource is also introduced.