Introduction

Annual repetition of consecutive developmental stages, collectively referred to as phenology, is a characteristic property of trees as large perennial plants. Seasonal patterns of development in forest trees, the dominant producers in terrestrial ecosystems, have a major influence on animal populations and ecosystem properties. In seasonal climates, most trees form new leaves and flower during relatively short, species-specific periods. In cold-temperate climates rising temperature induces synchronous leafing and flowering of all trees in spring (15), but the times of leaf flushing and flowering vary widely among trees of seasonally dry tropical forests (see Figure; 18, 23). Species-specific temporal patterns of seasonal development are the result of complex interactions between organ functions, such as leaf abscission or stem water storage, and environmental factors such as seasonal variation in rainfall, day length or soil water storage. This website summarizing our current understanding of these interactions was prepared mainly for the benefit of researchers in the tropics, who may have access to the Internet but not to a good library, and for others interested in the control of tree development in the tropics.

The control of vegetative and flowering phenology of tropical trees is addressed at four levels. At each level, lower levels can be accessed by clicking as indicated below. Return to higher level by clicking ‘Back’ on the tool bar.

• A schematic representation of common seasonal patterns of vegetative development and flowering (Figure). Click numbered circles to go to explanations of phenological patterns.
• A description and explanation of vegetative and flowering patterns shown in the Figure. Click numbers in parentheses to see references to the Literature.
• Titles of research papers analyzing the proximate causes of the described phenological patterns. Click Year to see a research paper in full.
• Complete text of research papers in pdf or Word format.