Table 3 Mean tree height (Column 2), net new height growth (Column 3), above-ground biomass (AGB; Column 4), below-ground biomas s (BGB; Column 5), root depth (Column 6), lateral root spread (Column 7) and total root length (Column 8) of willow and poplars grouped by clone, s pecies or planting type

Clone

‘Kawa’

3.93^a (0.47)

2.67^a (0.65)

3.0^a (0.7)

2.9^a (0.6)

0.6^a (0.0)

8.4^ab (0.3)

4.2^ab (0.3)

‘Veronese’

4.61^a (0.29)

3.74^a (0.10)

4.6^c (0.8)

2.8^a (0.5)

1.0^b (0.0)

7.5^a (0.8)

2.1^a (0.2)

‘Hiwinui’

5.10^a (0.27)

3.99^a (0.23)

7.8^b (1.8)

4.4^a (0.8)

0.6^a (0.0)

8.1^ab (0.1)

4.1^b (0.6)

‘Tangoio’

4.96^a (0.37)

4.00^a (0.20)

6.2^d (1.0)

4.8^a (0.9)

0.5^a (0.0)

10.0^b (0.3)

3.6^ab (0.5)

P value

0.083

0.094

<0.001

0.192

<0.001

0.031

0.032

Species

Poplar

4.31 (0.28)

3.27^a (0.31)

3.9^a (0.6)

2.9 (0.6)

0.8 (0.1)

8.0 (0.7)

2.5 (0.3)

Willow

5.03 (0.22)

4.00^b (0.15)

7.0^b (1.0)

4.6 (0.9)

0.5 (0.0)

9.0 (0.5)

3.9 (0.6)

P value

0.054

0.046

0.014

0.151

0.059

0.246

0.065

Planting type

Pole

5.39^a (0.33)

3.17^a (0.35)

9.0^a (1.3)

6.0^a (0.5)

0.6^a (0.1)

9.5^a (0.4)

4.2^a (0.4)

Wand

4.49^b (0.30)

3.89^b (0.29)

4.3^b (0.5)

3.1^b (0.2)

0.7^a (0.1)

8.1^a (0.6)

2.8^b (0.4)

Stake

4.09^b (0.16)

3.95^b (0.18)

3.0^c (0.2)

2.1^b (0.2)

0.7^a (0.1)

8.0^a (0.2)

2.6^b (0.1)

P value

0.006

0.034

<0.001

<0.001

0.660

0.063

0.014