Official website of the New Zealand Farm Forestry Association

Indigenous species - Black beech, Nothofagus solandri var. solandri

Species guide

Black beech is a strong, durable native hardwood that is found in cool forests from the Bay of Plenty to northern Canterbury. It is a relatively fast growing tree compared with other native species, reaching up to 30 metres high and up to 1 m in diameter. It lives for 300-400 years, tolerates cold and drought and will grow to altitudes of 600-700 m.

Black beech generates honeydew, which is favoured by bees and many native birds, but also (unfortunately) by German wasps.

Commercial return: Low


Site requirements

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Site preparation and planting

Black beech regenerates prolifically in natural forests and establishes well from seed. It has a relatively fast growth rate and is a suitable choice for native timber plantations in cooler climates.

Black beech seedlings are susceptible to drought and hard frost, and establish best if planted in partial shade/shelter such as within canopy gaps. Survival in the open may be enhanced by using short (0.6m high) shelters or a nurse species such as manuka established a few years before.

Prepare grass sites by spot spraying a one metre circle for each planting site. Use glyphosate herbicide with spray dye a few days before planting as this will not leave chemical residue in the soil. Prepare spots using straight lines and accurate spacings between spots so that trees can be easily found later. Cut down woody weeds and flatten these on the ground so they decay and don't support weed growth.

Planting

Trees are generally available from commercial nurseries as container grown stock. Price per tree should range from $2.50 - $5.00 for 1-2 year-old contract-grown forestry stock.

Plant as soon as possible after you receive the plants. Make sure the root plugs are moist and plant trees with a slow release fertilizer tablet or put a trowel of high nitrogen fertiliser such as DAP or urea in a spade slit above the seedling.

Dig a hole twice the size of the plant container, leaving some soft soil at the bottom. Tease out (straighten and trim) any pot-bound roots before firming the soil around them, ensuring there are no air cavities.

Black beech is a hardy pioneer species, but is frost tender on very cold sites when young and can succumb to drought conditions. On colder sites plant in early spring; in warmer areas with no hard frosts, plant from autumn.

Black beech will establish in open sites, but will have better form (taller and less bushy) and improved timber properties (fewer, smaller knots) if some side shelter is provided. A nurse species that grows fast initially but does not grow too big (e.g. manuka) can be planted to provide side shelter. The nurse crop should ideally be planted a few years before so that shelter is well established before planting the beech.

Spacing

Spacing for planting beech in an open site is 2 x 2.5 m (2000 stems per hectare). The higher the number of trees planted, the greater the selection ratio for retaining only the biggest, straightest crop trees.

If using a nurse crop, plant the nurse species at 2 x 4 m apart, then inter-plant with beech later at 2 x 4 m spacings.

See Successful establishment of tree seedlings »

See Site preparation and planting

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Establishment and Maintenance

Remember:

  • Prevent weeds from competing with the Black beech seedlings for at least three years after planting.
  • Protect seedlings from browsing by stock and wild animals.
Releasing

Ensure the newly planted tree gets enough light, moisture and nutrients to establish unimpeded. Maintain young trees by clearing or spraying weeds around them for at least two years or until they are well established and growing. Seek advice on choice of chemical if release spraying.

Native trees, being slower growing than exotics, may require releasing from weeds for several years so they don't become smothered by early weed competition.

During establishment Black beech responds to side shade by growing faster, straighter and taller with fewer branches. A nurse species that grows fast initially but does not grow too big, such as manuka, can be planted to provide side shelter. The nurse crop should ideally be planted a year or two ahead of the Black beech.

Overhead shade slows down growth. For good growth rates release trees from competing vegetation so some direct sunlight always reaches the tree’s leader. Climbing plants and dense woody weeds can overtop young native trees and may require manually cutting back to provide a light-well for the young tree to grow up through.

Where Black beech regenerates with manuka and gorse it will overtop these species within two or three decades, sooner if provided sufficient light.

See Successful establishment of tree seedlings »

Grazing/Browsing

Beech is susceptible to browsing by stock, goats and deer so fence the area to keep them out. A single hotwire electric fence will deter most cattle, but it is best to construct a full post and wire fence.

Beech is not a preferred food of possums but is palatable to rabbits and hares. They will slice off trees near ground level at a 45 degree angle, killing them.

Pests and diseases

A native pinhole borer attacks stressed or damaged black beech trees and moist harvested logs, drilling pinholes in the wood. Healthy trees will survive an attack but the pinholes can allow a fungal pathogen into the sapwood, which can damage the timber and sometimes kill the tree. In the North Island trees can also be attacked by the larvae of the puriri moth, which bore relatively large holes and also let in fungal pathogens. The kanuka long-horned beetle attacks saplings in both islands.

Many native leaf-eating insects feed on beech canopies. Red beech also attracts scale insects that feed on sap and produce honeydew, resulting in a black sooty mould growing on the excess nectar. The trees have evolved sufficient hardiness to survive most of these attacks.

See Beech, native Nothofagus spp. pests and diseases »

See Forest establishment and maintenance

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Management and silviculture

Black beech is among the faster growing of native species and is one of the more promising for plantation timber.

Suitability for steep slopes: Natural beech forests provide watershed protection. Although they tend to have shallow root plates the roots of closely spaced trees will interlock, making them wind-stable and suitable for exposed, eroding hill country. Black beech does not coppice: the stump dies when the tree is felled. See Report: Trees for steep slopes - Beech, Southern »

Pruning

If open grown under full light conditions Black beech will become heavily-branched with multiple leaders unless carefully form pruned. Close spacings provide better height growth and small branches but with a reduced diameter growth rate. Even at high stocking rates Black beech may require form pruning to grow straight.

Form pruning: If grown for timber, form prune at regular intervals to encourage a single dominant leader, and prune the trees every two years to prevent lower branches from getting too big. Pruning can begin once the trees are well-established and above the height of any competing weed vegetation – e.g. from around 2 metres tall.

Form pruning guidelines are available here.

Clearwood pruning: The aim of clearwood pruning is to minimise the defect core and produce wood free of knots. Pruning "lifts" must be regular and undertaken at a frequency that minimises branch size and diameter over stubs (DOS). Ideally, only final crop trees would be clear-pruned. The smaller more horizontal branches on lower stems of Black beech established within a highly-stocked stand (i.e. 1600 stems per hectare or more) will generally self-prune when they are shaded out. Larger, upward pointing branches should be removed as soon as possible as they will reduce height growth and increase defect core diameter.

Clearwood pruning guidelines are available here.

Pruning should be completed a year or two before thinning to reduce the likelihood of "epicormics" (shoots forming on the pruned stem). Pruning often attracts deer wanting to rub velvet from their antlers, resulting in ringbarking of the trees. Deer control is necessary to prevent this occurring.

Suitable pruning tools include loppers and a pruning hand-saw, a battery-operated reciprocating saw, or battery-operated loppers. Form pruning can be undertaken by using a pole pruner.

Thinning

Close spacings provide better height growth and small branches but with a reduced diameter growth rate. Thinning is required to reduce stocking (number of trees per hectare) and encourage diameter growth in residual "crop" trees.

Black beech trees are relatively light-demanding i.e. require light to grow well. However, if open grown, Black beech will tend to be heavily-branched.

Thin once the canopy has closed and before the trees get too tall, e.g. at 8–9 m in height. Stocking should initially be reduced to around 1100 – 800 stems per hectare (around 3–4 m apart) by removing poorer quality trees. Thin again once the canopy closes a second time, e.g. around 6 years later, to a stocking density of around 500 – 600 sph (approximately 4–5 m apart). The trees could be left at this stocking, or later given a third thin to as low as 200 sph (7 m apart)

When to harvest

A survey of beech plantations on a range of sites shows that mean diameters of 50 – 60 cm can be achieved within 100 years of planting. The owners of the Woodside property in Oxford, North Canterbury, have produced 45 cm diameter black beech sawlogs over rotations averaging 50 – 55 years. A 60 year rotation is suggested as a minimum for black beech and a continuous cover regime is recommended.

See Silviculture and forest management

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Timber utilisation

Black beech is a durable medium density hardwood with fine, straight grained and even textured wood, sometimes with handsome figuring. It is rich in silica and will dull saws and blades relatively quickly unless they are designed for this problem. It is relatively difficult to dry, shrinks in drying and may warp and split. However once dry it is strong and stable, machines well, is resistant to borer and can be used for flooring, joinery and furniture. The heartwood is ground-durable and was historically used for heavy construction and fence posts, while the sapwood was used extensively for building. Black beech heartwood is Building Code-compliant for durability in internal structural applications, flooring, exterior decking and weatherboards.

Harvested beech logs are quickly attacked by pinhole beetles and tend to check (split) unless milled soon after felling.

Markets and demand

Black beech is not a commonly traded timber.

Harvesting of Black beech is controlled by the Forests Act (and must be undertaken sustainably). Planted Black beech may be harvested for timber without controls if the owner has obtained a certificate from the Ministry for Primary Industries. The process is described here. 

More on black beech timber »

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Growth, yield, economics and carbon

Annual growth rates of planted black beech usually range from 30 to 60 cm in height and better than 1 cm in diameter (though it can put on 1 m in height and 2 cm in diameter on good sites). A survey of stands gave average heights of 16-17 metres 40 years after planting and 18-20 m at age 60. Samples measured 36 cm diameter at breast height (DBH) at age 40 and 46 cm DBH at age 60.

This paper offers some advice on monitoring growth.

Timber return on investment

No published calculations show return on investment for growing Black beech for commercial purposes. Although a simple calculation suggests earnings from carbon credits might overtake the costs of establishment after 20 years, this calculation is sensitive to every assumption and no claim is made that it is true or accurate. The assumptions used were:

  • Establishing 400 stems per ha at $5 per stem ($2,000 per ha)
  • Cost of capital 5% pa real
  • Lookup tables for indigenous forests apply: price of carbon $30 per NZU real 
  • Excluding the costs of land, rates, management and ETS compliance.
Carbon sequestration rate over time, and relevant Look-up Tables

If the land is registered under the Emissions Trading Scheme and the trees are planted so as to comply, i.e. at least one hectare, with tree crown cover of more than 30 percent in each hectare and an average width of tree crown cover of at least 30 metres, then they should earn carbon credits. The relevant look-up tables for determining how quickly they store carbon and earn credits, and guides to how to use the tables, may be downloaded here.

As Black beech is an indigenous hardwood, tables A2.2 and A2.4 apply, suggesting that over its first 30 years Black beech stores carbon at a rate of approximately one third as fast as radiata pine.

Outside the ETS this carbon calculator suggests how much carbon a planted native forest will store over time.

See Emissions trading »

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Further reading

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