Trees on farms Growing trees for timber

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1 Trees on farms Growing trees for timber Trees on farms, whatever their primary purpose, have the potential to deliver multiple benefits throughout their rotation. There are many examples where small woodlots, grown primarily for timber, have been successfully integrated with productive farming, providing benefits such as shade and shelter, soil conservation, and habitat for wildlife throughout their rotation. Planting land that is difficult to farm may also remove a management headache and make economic sense. As the trees mature they become a valuable capital asset and can help ease farm succession and retirement planning. At harvest farm woodlots can provide a cash injection as well as timber for on-farm use. First check that your trees are not toxic to animals Many trees available and for sale in New Zealand could be harmful to companion animals and livestock. Some of the tree species mentioned on the website below could, in some cases, cause issues in some animals. Before planting, make sure that you have selected the right trees. Check with your vet for advice or visit this site for a general list of toxic plants: tararuavets.co.nz What species can I grow for timber? Radiata pine is by far the most commonly grown species in New Zealand. It is a reliable performer and remains a viable option for farmers. Profitability depends largely on market conditions and harvesting and transport costs, which will vary with each site. Along with Douglas-fir, radiata pine is still the species of choice for larger-scale plantings on marginal land within economic distance to markets. Where land available for planting trees is limited, farmers may like to consider alternatives to radiata pine. There are many other species that grow well on the right sites, and yield potentially highly valuable and useful timber. Cypresses, eucalypts, redwoods, blackwoods, poplars, and a range of native species have all been grown successfully on farms. Markets for these timbers are developing, and there is good potential for use of timber on-farm and in homes. Classic farm forestry - radiata pine planted on a steep sidling, making good use of different land types. Page 1

2 Some options for farm-scale timber plantings Site available Some options to consider Species characteristics Rotation length (years) Potential end uses of timber Other key potential benefits while trees are growing Larger-scale steep slope or other areas which are marginal to farm too steep for the fert truck. Distance to market < km. Radiata pine or Douglas-fir Safe options to grow; established commodity markets for timber. Radiata Douglas-fir Appearance and structural timbers on-farm uses include fencing, buildings etc. Soil conservation, shelter, biodiversity, recreation. Field margin, corner or sidling, on dry site in low rainfall area and outside irrigated zone See photo SEQUENCE 1, page 3 Ground-durable eucalypts Fast-growing, very hard timber, can be used in-ground without chemical treatment Short rotations produce ground durable fence posts and poles including vineyard posts. Longer rotations produce durable sawlogs with many potential uses. Soil conservation, bees, biodiversity (some eucalypts are prolific flowerers in winter and spring), shelter, landscape and amenity. Steep slope, sidling or corner, relatively sheltered and fertile See photo SEQUENCE 2, page 4 Redwoods or cypresses* *Cypresses can cause abortion in cattle take care. Timber is higher quality and potentially higher value than radiata pine Weatherboards, decking, garden furniture, internal joinery. Soil conservation, shelter, biodiversity, recreation. Riparian margin, fenced and planted with natives See PHOTO 2, page 5 Scattered native timber trees e.g. totara, beech, matai, rimu, kauri The right native species on the right site can be surprisingly fast-growing. Versatile high-value timbers Furniture, internal joinery, flooring, structural timber, fencing. Biodiversity/amenity, shade and shelter. Sheltered steep gully, moist and fertile See PHOTO 3, page 5 Acacia (including blackwood), eucalypts, or native timber species High value decorative timbers. Blackwood Natives 70+ Furniture, interior joinery, flooring. Biodiversity/amenity, soil conservation. Erosion-prone hillside valued for grazing See photo SEQUENCE 3, page 4 Wide-spaced poplars (choose species with high density wood such as kawa ) Deciduous, fast-growing trees under which grass will continue growing at wide spacings. Versatile timber, light and strong Farm buildings, internal joinery, flooring and veneer. Export market potential. Soil conservation, shade, shelter, fodder, biodiversity. Page 2

3 SEQUENCE 1. Growing and utilising durable eucalypts A B From this - a durable eucalypt shelterbelt on a Hawke s Bay farm D To this. thinnings extracted from the shelterbelt C And this a pole barn built using farm-grown eucalypt timber E And this fence posts sawn from durable eucalypt on-farm and ready for immediate use. The most durable eucalypt timber will last for over 25 years in the ground, and over 40 years above it. 1e. And this eucalypt flooring products Page 3

4 SEQUENCE 2. Growing and utilising cypresses A B From this. macrocarpa on a south Canterbury farm To this. sawn macrocarpa timber D C And this home-grown macrocarpa joinery And this macrocarpa decking and planter box SEQUENCE 3. Growing and utilising poplars A B From this poplars stabilising a slope and providing shade and shelter To this a cabin built almost entirely of poplar Page 4

5 PHOTO 1 PHOTO 2 A riparian planting of kauri, Bay of Plenty A small stand of high-quality acacia beside a dam, North Canterbury Planning your planting With all tree planting, a long-term vision for your property is essential. Think about the whole farm, and the environment you would like to create for yourself and future generations. Think about farm operations, access, and possible infrastructure developments like new buildings and irrigation. Plan plantings carefully, bearing in mind that, with good design, you may be able to achieve multiple objectives. If growing timber is your primary objective, carefully consider the eventual harvest; good access is all-important. Sites with poor access may be better planted for other objectives. Select species to suit your site and any secondary objectives apart from timber. Look at neighbouring properties and see what is growing well; seek advice from reputable nurseries or experienced local farm foresters. When planning your planting, remember you may have to prune, and will definitely have to thin, your plantation. These operations need to be done on time; they take time and cost money, but if neglected, the opportunity to produce quality timber will likely be lost. A golden rule is to only plant an area of trees that you can manage it is always better to start on a small scale and do the job well. Before you plant Planting is normally a winter activity, but some sites may be better planted in autumn or spring, depending on species. Fence out livestock - keep sheep out until growing tips of trees are above browsing height; cattle and horses for much longer. If possible, graze the area to be planted hard before excluding livestock. Measure the planting area, and order trees from a reputable nursery well in advance Control problem weeds like gorse and blackberry Spot-spray planting sites to remove competing vegetation Control pests rabbits, hares, deer, goats and possums can all spell disaster to young trees. Try to minimise numbers before planting and keep numbers low thereafter Consider drainage of wet areas (or manage these areas differently by choosing different species) and ripping if soils are compacted. Be careful not to drain established wetlands. If you are unsure, ask your regional council. Page 5

6 How many trees do I need? The number of trees needed per hectare will depend on: the species the site whether genetically improved stock is available. Improved stock requires fewer trees per hectare. Spacing between trees (metres) /ha 1666/ha 1250/ha /ha 1100/ha 833/ha /ha 833/ha 625/ha Table: Common ranges of spacing and number of trees for most timber plantings Open spaces, such as tracks and space left between trees and fence lines, means the actual area to be planted could be up to 10 percent less than the total area available, so adjust tree numbers accordingly. After you plant Maintain young plantations: control competing vegetation by spot-spraying, which sometimes needs repeating over several years. A young totara spot-sprayed to prevent weed competition Good weed control and protection from rabbits and hares Form-prune: some species need form-pruning to encourage a single leader (main growing stem) to develop. Form pruning eucalypts to create a single leading stem Page 6

7 Clear prune: produces knot-free timber which is potentially the most valuable; most growers prune timber trees 2-3 times to a height of around 6 metres prior to harvest. Clear pruning cypresses to create knot-free timber. Timely pruning creates clear knot-free timber outside the pruned stubs. Thin: removes a proportion of trees so the remaining trees grow fat as well as tall. Most timber crops need to be thinned at least once, and sometimes 2-3 times during a rotation. Trees may be thinned to waste - left on the ground to decompose naturally; in some circumstances they can be production thinned and used, for example, for fence posts, sawn timber, or firewood. A young eucalypt plantation following a first thinning operation Example regimes for some farm forestry species Species Form prune Clear prune Thin Harvest Radiata pine N/A 2-3 times to reach 6m, years times, years Redwoods N/A 2-3 times, years 5-10 Once at age Eucalypts Year 1 and/or times, year times, years Totara Several times, years times, years Judicious thinning, years Page 7

8 Indicative costs Cost item Cost estimates (2015) Other considerations Fencing Electric fencing $5-$8/m Young trees and livestock do not mix. Ensure Post and batten fencing $13-$17/m fences are secure and check newly established plantations regularly. Trees Exotic species $50c-$4/tree Price per tree depends on species, size/quality Native timber species $2-$7/tree of stock and numbers ordered. Plant quality is more important than size small (25-50 cm) good quality plants are most cost-effective for timber plantings. Planting 40-70c/tree (contractor rates for bare-rooted trees). Expect to pay more for larger planting stock. Chemical weed control 25-30c/spot (1.4m 2 recommended) Some species need only one application; others such as natives and redwoods are often slower to get started and need repeat weed control Individual protectors Pruning Shelters $1-$3 each Some designs include a mat (to prevent weeds growing within the shelter) Approx. $2/lift trees per hectare are normally pruned (radiata pine) Suitable for small-scale plantings, especially natives, and if hares or rabbits pose a threat to young trees. Most species need 2-3 pruning lifts to achieve a 6-7 metre clear butt log. Thinning $450-$600/hectare Most plantings will need thinning at least once, and often more, to reach final stocking density. Final stocking depends on species, planned rotation length and target markets/ outputs. The end of the rotation While harvest-time may seem a long way off, bear it in mind before planting starts. Think about how the timber will be extracted and where it will be processed. If in doubt, seek professional advice on aspects such as roading and incorporate it into planting designs. More information The NZ Farm Forestry Association is the best source of information on growing trees for timber on farms. Join your local branch, learn from the experience of others, and visit their nzffa.org.nz Trees and the New Zealand Countryside: A planter s guide. John and Bunny Mortimer (1999), Taitua Books, Rotorua Page 8