Agronomic Performance and Nutritional Value of Native Forage Trees and Shrubs for Silvopastoral Systems in the Colombian Amazonian Foothills

The objective of this study was to evaluate the agronomic performance, forage yield, and nutritional composition of four native tree and shrub species from the Colombian Amazonian foothills Piptocoma discolor (PD), Clitoria fairchildiana (CF), Guazuma ulmifolia (GU), and Erythrina poeppigiana (EP) under planting spacing (PS: 0.25 × 1.5 m, 0.50 × 1.5 m, and 0.75 × 1.5 m), regrowth ages (AR: 30, 40, 50, 60, and 70 days), and seasonal conditions (less rainy and rainy). A randomized complete block design with split‐plots and four replicates was used. Significant three‐way interactions ( p < 0.05) were observed among species, regrowth age, and season for morphological traits (plant height, stem diameter, and leaf‐to‐stem ratio) and forage yield parameters (fresh weight per plant, dry matter [DM] yield per square meter, and projected annual DM production per hectare). PD recorded the highest projected DM yield (21.08 t ha −1 year −1 ) and fresh biomass (702 g plant −1 ), while GU had the highest DM concentration (27.8%) and wood density (1.40 g cm −3 ). Nutritional quality was affected by the interaction among season, species, and regrowth age. PD presented the highest crude protein content (up to 27.5%) and net energy for lactation (NEL) (up to 1.52 Mcal kg −1 DM) in early cuts (30 days) during the rainy season, whereas longer regrowth periods (70 days) significantly increased forage biomass. The profile of secondary metabolites varied among species and seasons: CF exhibited the highest tannin content, while PD showed the highest saponin concentration. These findings provide operational criteria for selecting and managing native species in sustainable silvopastoral systems under Amazonian foothill conditions.