2009 journal article
Animal and Pasture Productivity of 'Coastal' and 'Tifton 44' Bermudagrass at Three Nitrogen Rates and Associated Soil Nitrogen Status
AGRONOMY JOURNAL, 101(1), 32–40.
‘Coastal’ and ‘Tifton 44’ (T44) bermudagrass [Cynodon dactylon (L.) Pers.] are well adapted across the lower southern United States, but the grazing response of (T44) to N application in the Piedmont of the upper South warrants further evaluation. This 3‐yr experiment compared animal and pasture productivity of Coastal and T44 with three annual N rates of 101, 202, and 303 kg of N ha−1 on a Cecil clay loam (fine, kaolinitic thermic Typic Kanhapludult) soil typical of the Piedmont. Herbage mass differed for Coastal and T44 (3.5 and 3.0 Mg ha−1 respectively, P < 0.01), but not among N rates. The canopy of T44 was leafier (20.6 vs. 14.5% of dry matter) than Coastal and greater for in vitro true organic matter disappearance (IVTOD) (522 vs. 498 g kg−1) and CP (107 vs. 84 g kg−1) and lesser in NDF (596 vs. 605 g kg−1). The diet selected from T44 was greater in IVTOD (764 vs. 743 g kg−1) and lesser in NDF (596 vs. 605 g kg−1) giving greater steer average daily gain (0.63 kg vs. 0.57 kg; P < 0.01) which increased (P = 0.05) with N rate. Weight gain ha−1 (884 kg) and effective feed units (EFU) (4735 kg ha−1) were similar, and N rate linearly increased gain from 723 to 1073 kg ha−1 and EFU from 3978 to 5523 kg ha−1. Soil inorganic N was similar between cultivars but differed among soil depths. Tifton 44 pasture was greater in nutritive value, hence steer performance, and as productive as Coastal in the Piedmont.