42 www. sasmallholder. co. za
FIRE WATCH
Fire retardant... Ice plant From page 41
According to Brian van Wilgen, professor in the Centre for Invasion Biology at Stellenbosch University, there is some good news concerning wattles. The introduction of biological control to reduce the seed output of Australian wattles is having some effect. The introduction of a suite of seed-feeding weevils and gallforming flies and wasps( which prevent seed production by inducing the formation of galls instead of seed pods), has significantly reduced the seed output of many Australian wattle species. In the meantime though if you have any species of wattle mentioned above now is the time to cut them down. If you decide to cut down trees, be sure to remove whatever you have cut from the site so that there are no piles of dead material lying around. Then you are faced with the question of what to plant as replacement. Fire-retardant trees can offer protection from fire in three ways. Firstly, by acting as a shield against the immense radiant heat generated by an approaching fire, so that the house is protected from the intense temperatures that can shatter windows and melt materials. Secondly a large canopied tree or a strategically placed hedge act to trap the burning material carried in the intense fire winds. This reduces the amount of flaming matter that can reach and ignite the building itself. Finally the stored moisture in the leaves acts as all water does ~ it suppresses the fire ' s energy. Many times even a single tree has saved a house or shed. Plants with broad fleshy leaves and / or a high salt content burn much less readily than those with fine hard leaves. Bear these points in mind when looking at the trees around your boundary and the trees that surround your garden. The number of tall trees grown should be in scale to the property. Always plant with their mature height and width in mind. Wellmaintained evergreen shrubs and trees planted on boundaries can reduce fire intensity and wind speed, and deflect and filter embers. If trees are spaced so that their canopies aren ' t touching, this will help reduce fire spreading from tree to tree. Trees with smooth trunks are less flammable. Remove branches that could cause power line short circuits and check electrical installations regularly. Pay special attention to fuel load management in downslope areas and construct firebreaks adjacent to the property. Slash long grass and undergrowth and remove dead and dry branches from trees. Cut back or remove trees that are overhanging or touching a building.
Fire retardant... tree fuscia
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