1

Fig. 1. Visualisation of the methods used to identify the strip-road trees.

2

Fig. 2. Illustration of the original strip-road network (left figure) and three example offset sample networks from one stand (right figure). In total, 20 strip-road network positions were analysed stand-wise by shifting the network perpendicular to the strip-road direction in 1 m increments across the 20 m spacing.

3

Fig. 3. Stand-wise REI values for each strip-road tree identification method and the relative RMSE values for all stands. View larger in new window/tab.

Table 1. Hectare-wise stem counts of the reference data, original strip-road samples and offset strip roads showing the standard deviations (std) and minimum and maximum stem counts of the offset strip-road samples.
Measurement area Reference stem count
(n ha–1) 		Original strip-road sample stem count
(n ha–1) 		Offset mean stem count
(n ha–1) 		Offset stem count std
(n ha–1) 		Offset min–max count
(n ha–1)
A 1718 1525 1714 82 1537–1817
B 1250 1199 1253 73 1152–1400
C 1717 1534 1649 72 1548–1828
D 1654 1524 1649 73 1438–1776
E 1404 1288 1414 74 1289–1528
F 1435 1328 1443 105 1218–1604
G 1835 1699 1846 116 1661–2080
Table 2. Hectare-wise basal areas of the reference data, original strip-road samples and offset strip roads showing the standard deviations (std) and minimum and maximum basal areas of the offset strip-road samples.
Measurement area Reference basal area
(m2 ha–1) 		Original strip-road basal area
(m2 ha–1) 		Offset mean basal area
(m2 ha–1) 		Offset basal area std
(m2 ha–1) 		Offset min–max
(m2 ha–1)
A 24.5 19.8 24.7 1.2 21.5–27.1
B 16.1 14.5 16.1 1.5 13.6–18.8
C 24.7 20.4 24.5 1.7 21.4–26.2
D 24.7 19.3 24.6 1.2 21.1–27.0
E 23.7 18.5 23.9 1.3 21.4–26.4
F 22.0 19.0 22.1 2.2 18.2–26.8
G 26.4 21.7 26.5 1.8 22.4–29.8
4

Fig. 4. Hectare-wise stem counts and basal areas for each offset sample (solid blue line with dots), reference value (green dashed line) and original strip-road sample (blue dashed line).