Biology Reference
In-Depth Information
Box 3.4.
How wide should a planting be?
Many landholders have asked us how wide plantings should be to make them valu-
able for farm wildlife. As we have outlined in this chapter, any plantings on a farm,
even narrow ones (under 30 metres wide) are better than no plantings. Recent work,
however, is suggesting that some species of birds prefer to nest at least 17 metres
away from the edges of a planting. Therefore, a 40-metre wide planting would pro-
vide a band of just six metres of interior area within a planting (see Figure 3.13). This
indicates that plantings 40-60 metres or more in width will be those where nesting
is most likely to be successful.
We are aware that many plantings are narrower than 40-60 metres. This does not
mean they are without value, even though there may be some species which will not
nest successfully within them. Moreover, there may be opportunities to widen these
planted areas with additional rows of adjacent trees and shrubs or to link narrow
plantings with other plantings or patches of remnant native vegetation.
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intersections (see Figure 3.14) can significantly increase the number of species of
birds they contain. This means where there are space constraints on a farm that
might preclude the establishment of large block plantings, an alternative approach
Planting edge
17 m
Interior area
17 m
Planting edge
Figure 3.13:
The configuration of edge and interior areas for bird nesting success in a planting. (Drawing by
Clive Hilliker)
