Phenology of an 'immigrant' savanna tree (Acacia caven, Leguminosae) in the Mediterranean climate zone of Chile.

Abstract Phenological behavior was investigated in nine populations of the cold-deciduous legume tree, Acacia caven along three transects (36, 33 and 30°S) in summer-dry central Chile. Phenology was found to be uncoupled from rainfall patterns in this Mediterranean-climate region and out-of-phase with co-occurring plants. Its phenology, thus, more closely resembles that of many trees of seasonally-dry, subtropical savannas than that of typical Mediterranean-climate trees and shrubs. Cluster analysis revealed that significant phenological differences occurred between the four populations in the most arid transect (30°S), and the other five populations in the semi-arid and sub-humid zones further south, despite the absence of consistent morphological differences among these populations.