Pearl millet cultivar and seeding method effects on forage quality and performance of grazing beef heifers

In a 2-yr study, yearling beef heifers grazed pastures of two pearl millet (Pennisetum glaucum [L.] R. Br.) cultivars (Tifleaf 1 [TL1] or Tifleaf 2 [T L2]) planted with two seeding methods (conventional drill at 25 lb seed/acr e; or 3-ft rows at 5 lb seed/acre). Eight 2.0-acre pastures on Tifton sandy loam (fine-loamy, siliceous, thermic Plinthic Kandrudults) soil were used each year in the 2 x 2 x 2 factorial experiment. Four heifers (706 lb initi al body weight) grazed continuously for 84 d on each pasture, beginning 4 a nd 3 June in respective years. Additional heifers were used to vary stockin g rates In all pastures to maintain forage height at 18 to 25 in. cultivar did not affect (P > 0.10) ADG or gain/acre (TL1 = 1.50; 477 lb vs TL2 = 1.4 6; 454 lb). Seeding method did not affect ADG or gain/acre (P > 0.10), but grazing days/acre were higher for row than conventional drill (row = 847 vs drill = 751; P < 0.05). Heifer ADG and grazing days were affected by year, with higher ADG in 1992 than 1993 (1.64 vs 1.29 lb; P < 0.05), and more gr azing days/acre in 1993 than 1992 (350 vs 297; P < 0.01). A seeding method by, year interaction (P < 0.10) resulted in higher ADG and gain/acre for co nventional drill than rows in 1992 when rainfall distribution was more favo rable and similar performance an rows and conventional drill in 1993 when r ainfall distribution was less favorable. Esophageal steer pasture masticate in 1992 an d 77 had lower NDF for conventional drill than rows (27.3 vs 35 .8%; P < 0.05), IVDMD was higher for conventional drill than rows (70.8 vs 64.0%; P < 0.05). Seeding method affected forage quality and heifer perform ance, with rows being favored when rainfall was limited.