Uncoupled flowering and fruiting phenology as the strategy of non-native invasive woody species in seasonally dry ecosystems

Abstract

The timing of flowering and fruiting events is an important trait for explaining plant invasion. Seasonally dry ecosystems are characterized by a restricted growing season which imposes limitations on species reproduction. In these ecosystems to succeed, non-native species may have one of two phenological strategies. Coupled phenology with natives might be a product of an adjustment to environmental filters, exposing open flowers altogether, thus increasing the possibility of diluting some antagonist interactions but also mutualistic ones. Conversely, tolerating a wider range of environmental conditions might generate uncouple phenology, due to using a Vacant niche or having longer phenological periods. Previous evidence observed that non-natives have divergent strategies with natives in these ecosystems; thus, we expect to find uncoupled phenology. This uncoupled phenology may be associated with changes in the timing or length of the reproductive period. The aim of this work was to analyze the flowering and fruiting phenological strategies developed by the most frequent native and non-native woody species through a multi-year study. We measured the beginning and length of flowering and fruiting of sixteen species during four consecutive reproductive periods. We found that the phenology of non-native species was uncouple with natives. Non-natives showed a delay in flowering and fruiting and had a longer fruiting phenology period. Moreover, unlike the natives, non-natives fruited out of the growing season. The different phenological strategies found in non-native species may generate different interactions and windows of opportunities that may explain invasion and have profound consequences on ecosystem processes and functions.