16 Most timber farmers plant for ‘pulp wood’ rotations and select poles as an afterthought at clearfelling, resulting in less than 40% pole recovery, as shown in the example below. Average DBH:15-20cm 3 x logs of 2.4m Pulpwood 1 x log of 7.3m (50/100) 2 x logs of 2.4m Pulpwood = 30% Poles and 70% Pulpwood Silviculture Sites and Stocking: To achieve maximum pole recovery one must identify suitable sites to grow trees for specific markets. Building and fencing poles should be grown on poorer sites with a Mean Annual Increment (MAI) of less than 20 tonnes. These compartments can be planted at 1666 stems per Ha (2.5 x 2.5m or 3 x 2m) and felled at 5-6 years. Sites with MAI’s greater than 20 tonnes can be identified for growing transmission poles and planted at1666 stems per Ha. These blocks must be thinned at about 5 years to 700 stems/Ha. The thinning’s can be sold as small poles. Alternatively, plant at 3 x 3m and thin to waste at about 4 years. Thinning is done so that the stand produces large, high-quality trees which can be sold at a premium price. The number of trees per hectare affects yield and growth of trees, as do site quality and age. Thinning also helps to prevent stress which may induce pests and diseases. Clear-felling of transmissions can take place at ten years on very good sites and at 12 years on weaker sites. Coppice management: Compartments managed for building and fencing material can be coppiced for 1 rotation before replanting. Coppice should be reduced to 2 stems per stump. Compartments identified for production of transmission poles should be replanted after each rotation. Identifying and managing specific compartments on a timber farm for pole production will result in better pole recovery and profitability. However, pole markets tend to be dynamic and timber growers need to be flexible in terms of felling dates and product specifications to reap the full benefit of supplying these lucrative markets. Thinning of a compartment to allow trees space to produce transmission poles. Thinnings are sold for building and fencing.
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