Productivity and Quality of Bermudagrass and Orchardgrass‐Ladino Clover Pastures for Beef Steers1

Abstract

AbstractBermudagrass (Cynodon dactylon (L.) Pers.) has high potential summer forage production and can help fill the gap in foragebeef production systems during late summer. The productivity and quality of ‘Midland’ grown at four levels of N fertilization (0, 112, 224, 448 kg.ha) as forage systems for grazing beef steers were compared to those of common bermudagrass (C. dactylon var. dactylon) fertilized with 112 kg N/ha and of a mixture of orchardgrass (Dactylis glomerata L) and ladino clover (Trifolium repens L.) (Orc.‐Lad.). Pastures were grazed by a put‐and‐take system to maintain bermudagrass pastures at an average height ≥ 3.5 cm and ≤ 10 cm, and Orc.‐Lad. ≥ 8 cm and ≤ 15 cm. Forage growth and consumption were estimated by the cage‐and‐strip method.Forage production and animal performance were different in all treatments for the two periods April through June (spring) and July through September (summer). Average length of grazing season (23 April to 12 September) was not affected by N fertilization. Bermudagrass production was similar in spring and summer, and was increased greatly by N in both periods. Forage production of Orc.‐Lad. was twice as large in spring as in summer. Average stocking rate ranged from 3.7 steers/ha on Midland‐0 to 9.9 on Midland448 in April through June, and from 2.7 steers/ha on 0rc.‐Lad. to 14.3 on Midland448 pastures in July through September. Animal grazing days/ha for the entire season ranged from 546 on Midland‐0 to 1,759 on Midland448 pastures.Total beef production (kg/ha) was 162, 283, 350, 605, 308, and 561 from Midland‐0, ‐112, ‐224, ‐448, Common‐112, and Orc.‐Lad. pastures for the entire season, respectively. These values were associated with average gains (weighted for period within season) of 0.33, 0.41, 0.38, 0.44, 0.49, and 0.84 kg/steer/day and estimated forage dry matter intakes of 8.2, 8.9, 6.0, 5.7, 8.1, and 8.7 kg/steer/day, respectively. Most of the beef production occurred in spring. High stocking rates were necessary to harvest grazable forage and maintain grass in a young leafy stage in Midland224 and ‐448 pastures; thus, grazing selectivity was minimized and probably led to low intakes. Since 112 kg N/ha were not sufficient to produce acceptable quantities of forage or beef, a rate of 175 to 200 kg/ha on Midland is recommended for the future. At that N level, Midland will produce more than common which, at lower N levels, outproduced Midland.