Effect of Cultural Factors on Tall Fescue-Kentucky Bluegrass Sod Quality and Botanical Composition1
- J. R. Hall
Two field experiments were conducted on a Beltsville loam soil (fine loamy mixed mesic typic fragiudult) in Fairland, Md. to study the effect of mowing height, N timing, seeding date, and N level upon botanical composition, sod strength, sod transplant rooting strength, and the number of roots and rhizomes in sod seeded to 90 % certified ‘Kentucky-31’ tall fescue (Festuca arundinacea Schreb.)—10 % certified common Kentucky bluegrass (Poa pratensis L.). The mowing height × N timing study was conducted from 1972 to 1976 and the seeding date × N level study from 1973 to 1976. All plots were harvested as sod at maturity and transplanted on a prepared site to simulate normal harvesting and installation procedures. Plant composition was determined by point quadrant technique.
A 2.5-cm mowing height reduced tall fescue content 15 % (P < 2.5 0/0) at harvest when compared with the 7.5-cm mowing height. Mowing height had no effect upon sod strength or sod transplant rooting.
Split N applications applied from February to May, providing a total of 146 kg N/ ha, reduced tall fescue populations 21 % (P < 0.5 %) when compared with equivalent fall applications. Sod strength was not affected by N timing. Nitrogen timing treatments which supplied 73 kg N/ha within 90 days of harvesting significantly increased sod transplant rooting strength. Fall application of N significantly reduced smooth crabgrass [Digitaria ischaemum (Schreb) Schreb. ex Muhl.] invasion at the 2.5-cm mowing height when compared with spring fertilization.
August through September and March through April seeding dates increased the tall fescue content of harvested sod an average of 23 % when compared with October and November seeding dates (P < 5 %). Sod transplant root strength was generally highest in treatments with the greatest tall fescue content. Annual rates of maintenance fertilization, providing 73.2 to 219.6 kg N/ha, did not affect tall fescue content at harvest. High N levels reduced sod strength 21 to 24 %, depending on the time of sampling, when compared to low N treatments. High N levels increased sod transplant root strength 17 % (P < 0.5 %) when compared with low N levels. Sod cutting depths of 1.9 and 3.8 cm did not significantly influence botanical composition.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 1980. . Copyright © 1980 by the American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, and International Turfgrass Society, 5585 Guilford Rd., Madison, WI 53711 USA