Late Stages of Tropical Silvopastoral System: An Opportunity to Maximise Forage and Animal Production

Abstract

Silvopastoral systems (SPS) integrate pasture, trees, and animals in the same area and are alternatives for sustainable pasture intensification. We aimed to test whether, in the late stages of an SPS, with large but sparsely distributed trees (83 trees ha⁻¹), forage and animal productivity are comparable to a full sun pasture (FS) over an extended period. The study was conducted at Embrapa Southeast Livestock, São Carlos/SP, Brazil, from 2020 to 2023. The SPS consisted of Piatã palisade grass ([Urochloa brizantha] [Hochst ex A. Rich.] Stapf cv. BRS Piatã) pastures shaded by eucalyptus (Eucalyptus urograndis clone GG100) rows. The trees were planted in 2011, spaced 15 × 2 m (333 trees ha⁻¹) in a nearly east–west orientation, thinned in 2016 to 15 × 4 m (166 trees ha⁻¹) and further thinned in 2019 to 30 × 4 m (83 trees ha⁻¹). The FS was a Piatã palisade grass monoculture. Each system comprised four 3-ha areas divided into six 0.5-ha paddocks rotationally stocked with Nellore and Canchim (3/8 Zebu × 5/8 Charolais) yearling beef bulls (n = 32 [four/year. experimental unit]). Photosynthetically active radiation (PAR), forage accumulation and nutritive value, animal performance and productivity, and wood production were assessed. Post-thinning tree configuration resulted in only a 7% PAR decrease to the understory, supporting a live forage accumulation of 21,871 kg DM ha⁻¹ year⁻¹, compared to 25,373 kg DM ha⁻¹ year⁻¹ in the FS, and an animal productivity of 460 kg live weight ha⁻¹ year⁻¹—322% greater than the Brazilian average—for the three-year period. Additionally, the large trees produced 15.8 m³ ha⁻¹ of wood. Late stages of SPSs enable high forage and animal productivity over extended periods.