Predicting the vertical location of branches along Atlas cedar stem (Cedrus atlantica Manetti) in relation to annual shoot length

François Courbet (1) , Sylvie Sabatier (2) , Yann Guédon (3)

1 URFM - Unité de Recherches Forestières Méditerranéennes
2 UMR AMAP - Botanique et Modélisation de l'Architecture des Plantes et des Végétations
3 UMR DAP - Développement et amélioration des plantes

A model for the vertical location of whorl and interwhorl branches was constructed for Atlas cedar (Cedrus atlantica Manetti). The vertical location of branches in the crown partly governs their further growth and mortality from which depend (i) the stem growth and form and (ii) the quality of lumber and veneer, including wood knots. The modeling method, based on an architectural approach, reveals branching patterns. Each annual shoot was considered as a sequence of successive positions, unbranched or branched with two types of branch: short or long shoot. Branching sequences were analyzed using hidden semi-Markov chains. A wide range of annual shoot lengths was sampled in order to determine the relationships between sequence length and the characteristics of every zone identified (frequency of every type of axillary production, probability of zone occurrence and probability of transition to the following zone). The model predicts branch vertical position which can be used as inputs for branch diameter and mortality models.

Mots clés: Branching pattern; Branch vertical location; Hidden semi-Markov chain; Cedrus atlantica

Domaines: Biodiversité et Ecologie; Botanique

François Courbet, Sylvie Sabatier, Yann Guédon. Predicting the vertical location of branches along Atlas cedar stem (Cedrus atlantica Manetti) in relation to annual shoot length. Annals of Forest Science, 2007, 64 (7), pp.707-718. ⟨10.1051/forest:2007051⟩. ⟨hal-00191909⟩