Spatial distribution of seed yield was investigated in canopies of cv. Europe. The number of stems per class was variable across environments but whatever the canopy structure few stems had more than 11 mainstem inflorescences. The seed weight per inflorescence (SWI) for a given node increased with the number of fertile inflorescences. Along a stem, in a given class, it tends to decline at the upper position. A unique relationship was developed between the SWI and the position of the inflorescence counted from the top. The dominant stems give an adequate image of this relationship. The number of inflorescences carried by the branches of a given stem class is fully related to the number of mainstem inflorescences. The patterns were similar for different canopies with contrasting seed yield. Thus, there are strong physical and physiological rules regulating the seed yield elaboration within a canopy.