2 types of trees are available in Hi-sAFe

• evergreen trees
• cold deciduous trees

The phenology is represented by 4 stages:

1. budburst or leaves set-up
2. leaves expension end
3. leaves fall start
4. leaves fall end

Time of budding is characterized by a thermal time, the duration of foliar expansion is fixed, and leaf fall occurs when the mean temperature over the last X days goes below a threshold. All these parameters are fixed for each tree species.

For evergreen trees, a number of cohorts of leaves corresponding to a different group of age will be defined. On each cohort, a specific phenology development will be distinguished.

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