Forests once covered much of the Earth’s land surface. It was beneath this forest mantle that most of our plants and animals evolved and our soils were formed. In New Zealand, our wildlife and soils are seriously threatened by deforestation. Planting native trees in your pasture helps to offset this damage in two ways:

Erosion

Soils take millions of years to form but can be lost almost overnight. Trees, planted on vulnerable hillside pastures help to reduce soil erosion because their roots are stronger, and run deeper than grass roots.

Conservation

Small groupings of native trees create ‘habitat islands’ for wildlife. While poplars are good for controlling soil erosion and pines are good for timber, neither is especially good for supporting our wildlife. NZ native wildlife needs NZ native trees.

Years ago, when our pastures were cleared, an occasional forest tree was left standing for shelter and to retain something of the land’s natural beauty.

As these trees grow ancient and die, the barrenness of our pastoral landscape is increasing. Self-sown tree seedlings don’t survive under grazing so these forest-remnant trees cannot replace themselves. Planting small groupings of native trees in your pasture helps in two ways:

Shelter

Farm animals always cluster around trees if these are present. Trees provide them with shelter from excesses of heat, cold, sun, wind and rain and they also create for the animals a sense of security as research has shown. Farm animals are stressed without trees and less-stressed animals do better.

Landscaping

Large areas of treeless pasture are unnatural, whereas a pastoral landscape punctuated by native trees is easier on the eye and restores something of the old way for our grandchildren.

Establishing a tree in pasture is difficult. An isolated tree is very exposed to the elements and can be broken and scorched by the wind. Possums will eat the foliage. Cattle and sheep will chew the bark and will scratch against it, rocking it and breaking the roots. Planting, staking and protecting all demand special attention or mortality is high, wasting your tree, your money and your time.

Buy nursery raised, native trees of the species originally growing on your land. Stem diameter is less important, but trees must be healthy and also tall enough for their canopies to be out of reach of sheep (1.2 m) or cattle (1.7 m).

Stakes must be strong or they will break and well driven or they will loosen (~500 mm deep).

For sheep use a 50x50x1500 mm H4 stake (~$3), for cattle a 1,800 mm ½-round No2 post (~$8). Reject stakes having bad knots or crooked grain.

Dig the hole ~100 mm from the stake and ~200 mm deeper and wider than the rootball. Bury a loop of plastic drainage pipe with both ends to the surface. This allows quick dumping of water to the roots without wastage. Don’t tease out the roots. Add a slow-release fertiliser and backfill, firming well.

Tie close to the top of the stake to minimise chafing. Staple the tie to the stake to stop it slipping down, or up and off the top.

Water immediately and well to re-establish contact between roots and soil.

Weed spray 1 m all round to conserve soil water.

To protect from farm animals and possums use a modular tree protector that fits around both the tree and stake.

In the first year, apply water in especially hot or windy weather.

Spring growth soon develops too much canopy. Reduce windage and water usage for the first two years by early summer pruning.