Trees on the Farm The Farm Nursery

New Zealand Journal of Agriculture, Volume 95, Issue 2, 15 August 1957, Page 127

Trees on the Farm The Farm Nursery

MANY farmers will want to grow their IVI own planting stock either as a matter of interest or because of the several advantages of home-grown stock. Chief among these advantages is that the plants are fresh and available when the planter and the weather are ready for them. This article by W. H. Jolliffe, Extension Forestry Officer, New Zealand Forest Service, is presented to assist those who wish to raise their own trees, HOME-GROWN trees have the further advantages that they are becoming acclimatised to the locality from the time the seed germinates, that they are cheap, and that some specially good strain can be raised from personally collected seed. Any garden soil can be used for the purpose, and friability and good drainage are more important than high fertility. In fact, an over-rich soil will result in soft, lush growth that might not survive the greater exposure of the permanent site. The ground to be used for sowing this spring should have been deep dug last autumn in the same way as is usual for a vegetable garden. If saw-

dust has been used as a soil improver, a light dressing of a nitrogenous fertiliser such as sulphate of ammonia will assist decomposition. Other fertilisers should be used very sparingly, and then only if the soil is poor. If coniferous species are being grown, lime should not be added. The Seed-bed Though species with large seeds are sometimes sown in lines, tree seed is generally sown in raised beds. For convenience in weeding and wrench-? ing the bed is usually about 3ft. wide and whatever length is necessary for the required number of plants. The length needed can be calculated by assuming that 600 1-year-old trees or 150 2-year-old trees can be grown on each yard of -wide bed with three 6in.-wide bands. The surface of the bed is raised by scooping out the topsoil from the strips that will form the side paths and throwing this material on the bed area. Some weeks before sowing, the soil should be worked to a fine tilth and the surface raked level and free of stones. A final raking should be given just before sowing.

Sowing the Seed

* Spring (September or October) is the time for sowing. . Generally in a -wide bed 6in. bands separated by 6in. spaces are used. The bands are' made with a Sin.-wide plank, preferably one thicker than lin. This is laid along the bed 3in. from one edge and walked on. The plank is then placed 6in. from and parallel to the first band and again walked on. The process is repeated for the third band, which should have its outer edge 3in. from the other edge of the bed. The seed is spread evenly in these bands. The aim is to space the crop lin. x lin. if the trees are to be lifted as yearlings or 2in. x 2in. if they are to stay in the bed for 2 years. It is therefore desirable to know the germinative capacity of the seed being sown. If it is not possible to obtain this before sowing, the following table will serve as a rough guide for the commoner species. It is, however, an average of numerous results, so that considerable variation can be expected for any particular lot of seed.

NO. OF SEEDLINGS FROM lib. OF SEED Species Seedlings Radiata pine (Pinus radiata) 10,000 Corsican pine (P. laricio) . . 16,000 Ponderosa pine (P. ponderosa) . . . . ... 4,000 Macrocarpa (Cupressus macrocarpa) . . . . . . 7,000 Lawson’s cypress (Chamaecyparis lawsoniana) . . , 25,000 Douglas fir (Pseudotsuga taxifolia) .. ■ .. .. 15,000 Larch (Larix decidua) . . 6,000 Western red cedar (Thuya plicata) ... ' . . ... 60,000 Eucalyptus botryoides ‘ ... '. 120,000 E. viminalis . . .... 1,000,000 The seed spread in the bands should be pressed into the soil by pressure on the plank used in making the bands. The seed is then covered with sieved soil or sand to a depth roughly twice the. thickness, of the seed. If the soil is inclined to cake, sand is very much better for this purpose. Protecting the Bed Better results are obtained in most parts of the country if beds are protected in the early stages against drying by sun and wind, against unseasonable frosts, and against loss of seed by mice and birds. Usually this

protection is given by frames with side and end boards 6in. to Bin. wide over which is stretched coarse wire netting. This in turn is covered with open-mesh scrim, leafy branches, or slats held in place by wires stretched from end to end. Such protection tends to produce conditions similar to those on the forest floor and at the same time stops loss from the activities of mice and birds. The result is a . better strike and a bed which does not require watering except perhaps in an unusually dry spell. Weeding is necessary throughout the period from the sowing of the seed to the lifting of the young trees. Certain hormone weedkillers are claimed to be safe for application among conifers, but they should be used with caution. Later in the season the young trees have to be hardened off. . This is done by raising one side of the frame for a short time each day, the period of exposure being increased gradually until the frames can be removed completely. The final removal should be reserved for a dull or a wet day.