Biofriendly infrastructure

Roads, power lines and buildings take up biological space that would otherwise be occupied by plants and the organisms that depend on them. However, a great deal can be done to minimise this negative effect.   


The site is served by just over 2 km of road, all covered with a layer of blue metal (basalt chippings) to a width of 2.5 m. This implies that the area of road, 5,000 m2  (half a hectare) is clear of native biodiversity. This isn't quite true. For instance, some pigeon species obviously like it (picking up grit?). There is a worm that throws up large, wet casts, even at times when the topsoil is very dry. But the main biological our roads supply are seedlings. In particular, kangaroo apple (see photo), red ash, euodia and trema can often be found between the tyre tracks.


Power lines

Overhead power lines radiate to the sites of bores from a diesel generator. Trees have to be pruned so that their branches can't touch the lines. The best way to do this, from a biological standpoint, is to cut the trunks at ground level. This results in a dense coppice growth  that is low and bushy. Many native insects, including butterflies, prefer this young regrowth over mature foliage to browse on. It is difficult to get contractors to cut trees this low, however, rather than at waist height.

In a fertile rainforest environment, there is an inevitable progression to tall trees that are incompatible with overhead lines. However, either side of the lines, species that are naturally undershrubs in the forest can be planted. These include sandpaper fig Ficus coronata, callicoma Callicoma serratifolia, white bolly gum Neolitsea dealbata, brush bloodwood Baloghia lucida and bleeding heart Omalanthus populifolius.  These species have the added advantage that they respond well to pruning. 


We have bore sites that have substantial buildings on them, each surrounded by a cleared area to allow access for maintenance. A diesel generator is housed in two shipping containers placed one over the other. A number of bore sites that are used to monitor ground water are have just a pipe showing above ground. The Landcare group has two shipping containers for tools, mowers and a tractor. It has a covered table and water tanks, used for coffee breaks and visitors. 

The principal fear of the authorities controlling the bore sites is that they may be threatened by a bushfire. Fortunately, the climax vegetation of subtropical rainforest is not highly inflammable. However, some of the pioneer species that regenerate on the cleared fertile surrounds are. In particular, our wattles (Acacia irrorata, spectabilis, maidenii, prominens & schinoides) all become inflammable when they die. The are best removed from fire-sensitive sites while they are still young.   

Seedling kangaroo apples ready to be transplanted from the middle of the road.