Project Number: LAB03335 CRIS Number: 0177849 EFFECTS OF SILVOPASTORAL PRACTICES ON TIMBER, FORAGE, & LIVESTOCK PRODUCTIVITY IN COMMERICAL PINE

Investigators: Clason, T. R., Shilling, C. L., DeRouen, S. M., Mccormick, M. E., Walthall, M. P.

Termination Date: 03/31/2003
Reporting period: 01/01/1999 TO 12/31/1999

Progress Report:
The impact of silvopastoral practices on pine timber production, forage crop persistence and yield, and cow-calf production was evaluated in pine plantations (SP) and open pastures (OP). Bahiagrass (B) and common (CM) and Coastal bermudagrass (CB), and sod-seeded ryegrass (R) forage crops were established in both land areas and rotationally grazed. Forage fertilization treatments included low rate of nitrogen (LN; 2 applications at 56 kg/ha) and high rate (HN; 4 applications at 56 kg/ha). Four forage management treatments SP-LN, SP-HN, OP-LN, and OP-HN were replicated 6 times for forage production. Ten F1 Brahman x Hereford cows with Angus-sired calves were assigned to each land type x fertilization regime with animal production replicated four times by year. All cows were commingled over the winter prior to treatments assignment. An Angus bull serviced each of the four herds from May 1 to June 30. Cows were palpated for pregnancy status on October 12. Mean 210 day total forage dry matter yield was 13510 kg/ha with SP and OP yields being 12250 and 14770 kg/ha (P=.21); LN and HN yields were 13540 and 13680 kg/ha. R dry matter yields averaged SP 5500 and OP 6770 kg/ha(P=.22). Mean warm-season yields were SP 6750 and OP 8000 kg/ha (P=.27). Neither fertilization treatment nor crop type affected warm-season forage yields. B, CM, and CB mean yields were 12620, 11560, and 12590 kg/ha for the SP land type (P=.19); and 14890, 13620, and 15650 kg/ha for the OP land type (P=.18). Although SP forage yields were 15 percent less than OP yields and drought conditions required cattle assigned to SP-LN and SP-HN pastures be moved to an adjacent pine plantation on August 30, animal production was not affected by forage management treatments. Cow winter (January to April), spring (April to June), and summer (June to October) weight changes, and pregnancy rate for SP-LN, SP-HN, OP-LN, and OP-HN were: -4, -9, -43, and -18 kg (P<.01); 3, -10, 13, and 8 kg (P<.01); -22, -8, 5, and -16 kg (P<.02); and 100, 92, 100, and 75% (P<.02), respectively. Treatment differences (P<.04) in cow body condition score changes occurred only during the spring and were: -.30, -.08, .31, and .33 for SP-LN, SP-HN, OP-LN, and OP-HN, respectively. Calf winter, spring, and summer daily weight gains, and 205-day weaning weight for SP-LN, SP-HN, OP-LN, and OP-HN were: 1.16, 1.10, 1.12, and 1.17 kg (P=.57); 1.05, 1.05, .97, and 1.14 kg (P=.11); .94, .90, .89, and .88 kg (P=.75); and 251, 242, 242, and 249 kg (P=.81), respectively.

Publications: (3)
Clason, T. R. and S. M. DeRouen. 1999. Calf production on a loblolly pine silvopasture. p. 27. In T. R. Clason (ed.) Abstracts: The Sixth Conf. on Agroforestry in North America, June 1999, Hot Springs, AR.

Clason, T. R. 1999. Silvopastoral practices sustain timber and forage production in commercial loblolly pine plantations of northwest Louisiana, USA. Agroforestry Systems 44:293-303.

Clason, T. R. 1999. Silvopastoral practices sustain forage production in commercial loblolly pine plantations. p. 97-101. In L. E. Buck and J. P. Lassoie (ed.) Proc. Fifth Conf. on Agroforestry in North America, Aug. 1997, Ithaca, NY.

Impact:
Although tree overstory reduced the mean 210 day daily forage dry matter yields by 15 percent, similar productivity was achieved for cow calf production in the silvopastoral pastures versus open pastures with identical stocking rates. Drought conditions resulted in limited forage availability during the last month of the preweaning phase in the silvopastoral pastures.