The natural tree
The best season to lift a wild tree is the early spring. The necessary tools are a small spade or strong trowel, secateurs, a saw, a strong knife, plastic bags or polythene sheeting, sphagnum moss, scissors and string.
When collecting from nature there are three essential rules: First find a suitable tree; second, always secure the owner's permission before removing it; and, third, be sure that it can be looked after: Wild trees, unless little more than seedlings, need almost constant care for the first few months, as the shock of transplanting is considerable.
The first step is to dig a trench around the tree at the farthest extent of its branches. The roots of normal trees extend this far; the roots of dwarfed trees have often been forced to seek nourishment much farther from the main trunk. Avoid cutting roots over half an inch in diameter until the trench is complete.
Once the trench is dug, cut all the roots over half an inch in diameter. All roots should be cut so that the cut slants in at the bottom, helping to prevent moisture lying on the wound. If the soil is firm, and there are plenty of small roots near the trunk, grasp the root-ball in both hands and gently rock it to and fro. If there is no tap root the tree can be lifted almost straight out; otherwise the tap root should be cut as low down as possible. The tree should then be studied carefully and all unnecessary foliage and branches be trimmed out. This gives the roots a chance to recover and reduces the surface area that can lose moisture.
If the tree has only a few hair roots close to the trunk and the main roots are thick and long, it will be at least a year before the tree can be lifted with safety. Cut only half the roots on the first visit, leaving the others undisturbed; fill the trench with John Innes or similar potting mixture. After a year - and providing that the fine ciliary roots have grown sufficiently - the remaining roots may be cut and the tree lifted. Some specimens, especially the older pines, may have to be left longer, the roots being cut over a number of years.
Once the tree has been lifted, large wounds on the roots should be sealed with proprietary sealant, as used in tree surgery. Pack damp sphagnum moss around the root-ball and keep it in place with a plastic bag. Another large plastic bag put over the top of the tree slows down evaporation during the journey home.
The tree can be planted straight into a training pot if the root-ball is small enough; otherwise it should be planted in the open ground for a year to allow the ciliary roots a greater chance to develop. Pruning should be carried out whenever necessary, but do not attempt any training with wire during the first year. After replanting, the tree should be protected from strong wind, heavy rain and harsh sunlight, and sprayed with cold water at least twice a day for three months.
Shelter and display
Although most bonsai trees are hardy, prolonged frosts can occasionally cause damage to the more delicate varieties, and winter protection should be given to them. This need be little more than bringing the tree into a cold garage or even turning a small cardboard carton over the top of the tree. However, to help both the outdoor display of the trees and their seasonal protection, it is well worth constructing a more lasting display bench in a quiet corner, preferably against a western hedge or fence.
The number of trees in the collection will determine the size of the stand. When calculating the dimensions, be sure to allow each tree plenty of space. To allow for easier working the stand should be made a little higher than an indoor table. It should be made of good quality wood, treated with a preservative, or it could have a metal frame with a wooden top. The trees can be placed on a gravel bed as this cuts down on the need to water; but in this case they should be lifted every now and then to make sure the roots are not growing into the gravel.
Above the stand, around the sides and at the back a weather-shade of thin timber laths or canes should be made. Each strip should be secured an inch apart. This will help protect the trees from all extremes: hot sunlight, heavy rain, high winds and even a certain amount of frost. For harder winter conditions the bottom of the stand can be enclosed and the trees placed inside. A tool drawer or rack can be incorporated under one end.