Table 1. Characterization of sampled seed trees: zone of origin, generation, circumference at breast height (in cm), male flowering intensity (using a 0–3 scale), and local density.

Tree	Zone	Generation	Circumference	Male flowering intensity	Local density
A102	Z1	G0	291	2	5.8
A107	Z1	G1	198	3	6.6
A110	Z1	G0	285	1	7.3
B112	Z1	G1	144	1	5.6
B115	Z1	G1	134	3	3.5
B118	Z1	G2	117	0	4.0
B119	Z1	G1	144	2	5.2
C105	Z1	G2	63	0	2.5
A202	Z2	G0	203	2	4.9
A206	Z2	G0	243	2	6.4
A214	Z2	G0	263	0	7.1
B201	Z2	G1	149	0	13.5
B205	Z2	G1	159	0	6.9
B206	Z2	G1	100	0	6.1
B213	Z2	G1	96	0	5.8
B216	Z2	G1	149	3	7.0
B219	Z2	G1	92	0	6.1
C201	Z2	G2	58	0	5.5
A307	Z3	G0	219	3	12.9
A310	Z3	G0	245	1	7.1
Mean (s.d.)			167.5 (72.0)	1.2 (1.2)	6.5 (2.6)

In relation to the age class, G0 included the founder trees planted in 1863, G1 was the first generation issued from G0, and G2 was the next generation that issued from G0 and G1 (Lefèvre et al., 2004). Local density was measured as the mean distance from the seed tree to the five nearest neighbour trees (in metre).