The propagation in nurseries of native plant species potentially useful for agroforestry, silvopastoral and restoration programs is hindered by an inadequate supply of high quality seed. Limitations in our knowledge on the phenological patterns of native species result in the lack of efficient collecting protocols. Here we analyze the reproductive phenology of 14 native tree species from Seasonally Dry Tropical Forest (SDTF) that are widely used in reforestation and restoration programs. We conducted monthly observations during five years through a community-based monitoring program in two conservation areas within the Zicuirán-Infiernillo Biosphere Reserve (West Mexico) to assess the flowering and fruiting phenology of 149 marked trees (7-20 trees per species). For each species we described the phenophase intensity, duration, seasonality, synchrony and frequency. We related the intensity of reproductive phenology to climatic variables (photoperiod, precipitation and temperature). We identified three main phenological strategies of SDTF species that differ in timing and climatic triggers: (1) flowering and fruiting exclusively in the rainy season; (2) flowering in the rainy season and fruiting in the dry season; and (3) flowering and fruiting exclusively in the dry season. For each phenological strategy we make recommendations of optimal collecting seeds schedules. The community-based monitoring program, which involves the participation of local social actors, guaranteed the success of long-term phenological monitoring. Our study provides valuable information on both the inter-annual and inter-specific variation of the phenological patterns of tree species of forestry interest, and demonstrates that qualitative descriptions of population-level phenological attributes is an essential input to develop adaptive management programs.

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The great phenological diversification characteristic of seasonally dry tropical forests (SDTF) suggests that these patterns result from a complex interplay between exogenous (e.g., climatic) and endogenous (e.g., morphological, physiological, anatomical) factors. Based on the well-established relationships of wood density with waterstoring capacity and cavitation vulnerability in woody plants, we hypothesized differential vegetative and reproductive phenological responses to environmental cues for hardwood and softwood species. To test this hypothesis, we compared phenological patterns of pairs of conspecific populations of 10 species differing in wood density, occurring in two localities with slightly different climatic regimes, and evaluated the influence of three environmental variables (rainfall, photoperiod, and temperature) on them. Our results, based on the assessment of the overlap of the phenological curves of conspecific populations occurring in different sites and on linear modeling, showed different effects of the environmental factors on phenophase attributes, depending on wood density of the study species, thus supporting our hypothesis. Leaf out in softwood species took place in the dry season, they shed the foliage at the first signs of drought, and once leafless, they flowered and fruited shortly after. By contrast, hardwood species bore leaves and flowers in the rainy season, shed their leaves several months after the rain ceased, and produced fruits during the dry season. We conclude that the role of environmental variables in cueing growth and reproduction cycles in SDTF tree species is interrelated with their wood density, a key endogenous factor crucially linked to plant hydraulics in these water-limited ecosystems.

SummaryCommunity nurseries within natural protected areas (NPAs) represent an attractive option to link biodiversity conservation with socioeconomic development, yet their functioning lacks proper assessment. Here, we analyse the national context of community nurseries in Mexican NPAs and suggest a specific framework to evaluate their viability. First, we examine the impact of a major governmental funding programme on these projects. Next, we conduct a case study in a focal nursery to identify challenges faced by its operation. Despite the large number of community nurseries funded by the programme, current performance indicators are not suitable to assess their viability. In turn, the case study reveals this nursery’s partial success, with a clear contribution to social development but a limited impact on economic improvement and vegetation conservation. Regardless of the characteristics of individual community nurseries, we suggest a framework that is potentially useful for evaluating community nursery viability, which enables agencies to detect problems, find solutions and use resources efficiently, while balancing biodiversity conservation and development.