A tree distance-dependent growth and yield model for naturally regenerated pure uneven-aged maritime pine stands in central inland of Portugal

Table 2 Summary statistics for the data collected in open-grown trees identified in the study area

Tree variable	Symbol (units)	n	Min.	Max.	Mean	Std. dev.
Diameter (dbh)	d (cm)	52	9.3	38.2	20.4	8.1
Height	h (m)	52	4.6	17.5	8.8	3.2
Crown width	cw (m)	52	1.9	7.1	3.5	6.4
Height to the crown	hc (m)	52	0.2	4.7	1.9	1.2
Crown ratio	cr	52	0.63	1.96	0.80	0.1
Age	t (years)	52	7	33	18	1.2
Diameter increment	id5 (cm year⁻¹)	52	0.4	1.8	1.0	0.4

ISSN: 1297-966X