Warming promotes growth of seedlings of a woody encroacher in grassland dominated by C₄ species

Little is known of warming effects on growth and defence woody seedlings that potentially invade grasslands. We predicted elevated temperatures would increase spine length Vachellia sieberiana growing (1) with or without grass in the dormant season early season, but (2) only when cover absent mid-late season. To test these predictions, 120 were grown 20 field plots middle late Ten warmed open-top chambers raised air temperature by 1.0 to 2.5 °C depending Warming generally increased metrics regardless across seasons was absent. The results imply under a warmer climate, V. will thrive irrespective cover.