Effects of Various Nitrogen Sources, Timing, and Rates on Quality and Growth Rate of Cool-Season Turfgrasses1
- F. B. Ledeboer and
- C. R. Skogley2
Fertilizer applications to cool-season turfgrasses usually consist of treatments in spring, summer, and early fall. Two field studies were designed to compare various fertilizers at different timing and rate schedules on several cool-season grasses alone and in mixed stands. A 10-2.6-3.3 (30% org. N) fertilizer was used at .5, 1.0, and 1.5 kg/ARE in single and split treatments in May, August, September and late November. Ammonium nitrate (AN) and ureaformaldehyde (UF) were compared at equal rates on ‘Merion’ Kentucky bluegrass (Poa pratensis L.). A total of 1.5 kg/ARE was applied in split treatments during the same months as stated above. Turf quality ratings were taken for three seasons, and bi-weekly clipping weights, for two full growing seasons.
Growth and color responses were correlated with fertilization rates in the first study, but at all three rates, fall and late fall treatments resulted in more uniform turf quality and less clipping weights than with comparable spring and summer fertilization. Calculated CV values were consistently lower for both parameters. Grasses maintained better winter color and greened up earlier in spring. Results with AN in the second study were similar, while UF treatments failed to produce satisfactory turf at the tested rate. Fall and late fall AN applications regularly maintained acceptable turf within acceptable clipping limits.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .