Introduction to Glenhope Agroforestry
Fun and Profit with Agroforestry
Cost and potential returns
To establish a farm forestry plantation costs between $1,000 and $3,000 per hectare, depending on area, number of trees, fencing and other ground preparation required. Initial stocking is 1,000 trees per hectare. Maintenance averages $200/ha per year over rotation period, which includes silviculture (pruning and thinning ie removing trees). Once final pruning height and final stocking is reached, further work and costs are minimal. Plantation FF1 has almost reached this stage (refer Strategy page).
Harvesting 150 stems each 5m clearwood long x 60cm DBH (Diameter at Breast Height measured at 1.30m above ground) , depending on species, could yield $22,000 to $38,000 per ha at 2011 values. Current stocking of FF1 is 200 stems/ha. Adding value by felling, de-limbing, removal from forest, milling, drying, making products like flooring, posts, firewood, furniture, selling direct to retail customers, increases returns by 2 to 20 times stump price.
Whether trees are clear felled (all of them) or substantially thinned (harvest 50-75%), eucalypts will coppice (regrow from stump) and can then be harvested again and again, saving re-establishment costs and initial establishment time, as future rotations will be several years shorter that the initial one.
Where is the Fun?
It's in the management and watching the landscape change. Take a look at the galleries to see the before and after on our property. To get a good profit, you need to plant suitable trees and manage them for quality timber. The most profit is realised from sawlogs, knot free timber, and this requires regular silviculture - form and stem pruning (removing branches), thinning (removing inferior trees to boost growth on best trees). Growing trees purely for posts, firewood or pulp requires less maintenance, but realises a much lower profit. However, you can produce these products when you thin the plantation.
You can do the management yourself or get professional help. It involves healthy work in the fresh air, surrounded by magnificent scenery. We use a combination of self and professional help. In our experience, professionals are better and quicker at dispassionately selecting the right trees to prune or thin. It's emotionally hard to remove a tree, which you have planted but it needs to be done to make quality timber from the final selected few. Final stocking of 100-200 stems/ha involves removal of 80-90% of the original planted trees. The resulting forest is magnificent with straight trees widely spaced and pruned to 6.5 m in height with smooth knot free stems topped by a canopy (known as the crown), which cools the ground underneath on a hot day.
Forests and woodlands provide shelter to crops and livestock from cold or hot winds and heavy rain. Forests support wildlife and understorey flora, which provide habitat for insects and birds, which in turn feed off pests which can affect crops including the trees. Trees combat erosion and reduce high water table which causes dryland salinity and prevents useful crops and grasses from flourishing. Grassed areas between the woodlands act as firebreaks. Vigorously growing trees have lower fire risk than remnant native stands. Livestock prune lower branches of trees, preventing them becoming too thick in the early years and making the forests more accessible. Livestock also keep the grass around the trees and in firebreaks short so there is even less fire risk. Pruning trees up to 6.5m and thinning also further reduces fire risk as the forest grows, since there are no lower branches to catch fire.
Before the fire danger period started Dec 2011, I burned off excess grass in several ungrazed plantations and was amazed at the fire resistance of the trees. Despite a significant fire, there was no damage to the important trees.
Although, one of the original objectives was to plant for profit and this remains the case, this objective has been pushed into the background as time has passed and the effects of the plantations on the landscape generally and property specifically have become apparent. I've realised that I can use agroforestry to rehabilitate degraded land and improve both the aesthetics and productive capacity of the land. In 2001 the property had ca 10 hectares affected by dryland salinity. These hectares were covered with Spiny Rush, a noxious weed imported many years ago by the government from South America to fix erosion problems. This weed was sprayed over several years at great expense but it was the establishment of plantations, which is finally fixing the problem by lowering the water table and preventing the spiny from growing.