Rays in juvenile wood of Acer

Juvenile wood characteristics of multiseriate and uniseriate rays of five s pecies of the genus Acer were studied on young trees from France and Canada . Ray height, width, number in width of cells and proportion/mm(2) were det ermined for the earlywood. Variance analysis was used to discriminate the v ariability of the characteristics of rays. Simple regression analysis shows some strong correlations between the characteristics of multiseriate and u niseriate rays of each species. Except for A. saccharinum, no relationships were established between the ray characteristics and the specific gravity. Except for A. pseudoplatanus, no relationships were established between an nual ring width and ray characteristics. Principal component analysis focus ed separately on multiseriate rays and on uniseriate rays revealed differen ces between A. saccharum and A. saccharinum (e.g., the proportion and the n umber of cells in multiseriate rays).