Your privacy, your choice

We use essential cookies to make sure the site can function. We also use optional cookies for advertising, personalisation of content, usage analysis, and social media.

By accepting optional cookies, you consent to the processing of your personal data - including transfers to third parties. Some third parties are outside of the European Economic Area, with varying standards of data protection.

See our privacy policy for more information on the use of your personal data.

for further information and to change your choices.

Skip to main content

Table 5 Means and standard deviations (in brackets) and percentage of variables considered for the tree-quality assessment by species

From: Improving stem quality assessment based on national forest inventory data: an approach applied to Spanish forests

Species

N plots

N trees

dbh

H1Abranch

H1Dbranch

Crown H

% SG

% Pruned

P. sylvestris

1624

7169

30.1 (9.9)

6.7 (4.0)

3.3 (2.6)

7.6 (4.0)

0.2

16.9

P. nigra

535

2224

26.1 (7.3)

5.4 (2.8)

2.6 (1.5)

6.0 (2.9)

0

32.0

P. pinaster

2021

8058

33.7 (10.1)

6.7 (3.2)

3.9 (2.3)

7.2 (3.3)

0

18.5

P. radiata

64

279

33.8 (12.8)

6.5 (3.6)

2.3 (2.1)

8.3 (4.1)

0

30.1

Q. robur

20

63

37.4 (17.8)

4.3 (1.9)

4.3 (2.2)

6.2 (2.2)

0

0

Q. petraea

147

569

32.6 (14.5)

4.9 (2.8)

4.2 (2.3)

6.9 (2.8)

0.4

0.4

F. sylvatica

298

1210

30.8 (13.0)

4.1 (2.7)

4.4 (2.6)

6.0 (3.0)

0

0.1

C. sativa

74

227

30.4 (14.4)

4.4 (3.2)

3.2 (1.8)

7.1 (3.1)

0.4

7.0

  1. N plots number of plots sampled per species, N trees number of trees sampled, dbh mean diameter at breast height (cm), H1Abranch and H1Dbranch mean height of the first living and dead branch, respectively (m), Crown H crown height (m), % SG percentage of trees with spiral grain (dichotomic variable 0/1), % Pruned percentage of artificially pruned trees (dichotomic variable 0/1)