SHELTER-BELTS AND HEDGES AT RUAKURA.

New Zealand Journal of Agriculture, Volume XXVI, Issue 3, 20 March 1923, Page 133

SHELTER-BELTS AND HEDGES AT RUAKURA.

THE EXPERIENCE .OF TWENTY YEARS

A. W. GREEN,

Manager, Ruakura Farm of .Instruction, Hamilton.

A T OW that the Ruakura Farm of Instruction has been established V for almost twenty years, it is possible to give some valuable in-, formation regarding the various shelter-belts and hedges planted during the. early years of development. Fortunately, in the first place, the trees in these belts were well selected and planted in proper order, and since then have been well cared for. In every case wire fences protecting the trees from live-stock were ■ erected, and have since been kept in sound repair. The planting and cutting-out later of nursetrees is another factor which certainly has had a great influence over the present excellent state of these shelter-belts. Those who have had experience in the growing of trees on windswept areas fully' appreciate the value of quick-growing nurse-trees. They protect the slower-growing and more permanent trees from strong winds, draw them up straighter, and encourage more rapid growth. On the other hand, nurse-trees must not be allowed to remain too long in the shelters, and thinning-out is work which must be attended to at the right time. Many properly planted shelterbelts are ruined by allowing nurse-trees to remain too long. They

then overcrowd and finally kill the permanent trees, especially if such nurse-trees as pines are 'used. At Ruakura it has been found that Pinus muricata makes a most suitable nurse-tree in the shelter-belt. This pine is not so liable to overcrowd and will not rob the permanent trees to the same extent as Pinus insignis. , Other trees thrive well when growing in close proximity to Pinus muricata, and it has remained very free from pests and diseases, which is an important matter. Pinus halepensis (Aleppo pine), Pinus rigida (American pitch-pine), and Cryptomeria elegans have been used to some extent, but in this district all have taken disease badly, and for this reason cannot be recommended: On poor lands Pinus insignis succeeds well as a nursetree, but care must be taken to cut it out immediately the permanent shelter-trees are sufficiently advanced to allow of thinning. It must be recognized that nurse-trees have other uses. They make good firewood, and at this station have been the main source of supply. TREES AND SHRUBS WHICH HAVE GIVEN, SATISFACTORY RESULTS., At Ruakura the following trees have thriven and been found useful; they can be recommended for places with similar conditions : (i.) Trees suitable for a high single-row hedge: Cupressus Lawsoniana (Lawson’s cypress), Cupressus Benthamii, Cupressus Knightiana, poplars and Cupressus Lawsoniana combined, poplars and Pseudo-tsuga Douglasii (Oregon pine) combined. (2.) Trees suitable for a low single-row shelter hedge: (a.) Field hedges ßerberis (barberry), Eleagnus japonica, barberry and Eleagnus mixed, Cupressus Lawsoniana (well clipped).- (&.) Garden or section hedges Junip crus communis hibernica (Irish juniper), Ligustrum sinensis (Chinese privet), Pittosporum Ralphii, Pittosporum tenuifolium, Cupressus Lawsoniana (well clipped), Podocarpus totara (totara), (well clipped).

(3-) Trees suitable for mixed ornamental and shelter belts, planted three or four rows deep: (a.) Evergreen trees Cupressus macrocarpa, Cupressus Lawsoniana, Cupressus Benthamii, Sequoia sempervirens (Californian redwood), Wellingtonia gigantea (Californian mammothtree), Thuya gigantea (Oregon white - cedar), Pseudo-tsuga Douglasii (Oregon pine), Quercus sempervirens (evergreen ’oak), Pinus strobus (Weymouth pine). (&.') Deciduous’ trees -Betula alba (white-birch), Larix europaea (English larch), Fraxinus excelsior (English ash), Quercus robur (English oak), Juglans regia (English walnut), Juglans Sieboldiana (Japanese walnut). (4.) Trees suitable for planting in belts or corners for posts: Eucalyptus Macarthuri, Eucalyptus fastigata. (5.) Trees suitable for planting in blocks for timber: Pinus insignis, Cupressus macrocarpa, Sequoia sempervirens, Eucalyptus Macarthuri, Eucalyptus fastigata. (6.) Shrubs and trees suitable for an ornamental shrubbery of native, trees: Griselinia littoralis, Pittosporum Buchananii, Pittosporum Ralphii, Pittosporum tenuifolium, Olearia furfuracea, 01 earia nitida, Persoonia toro, Panax arboreum, Hoheria pqpulnea, Sophoro tetraptera (kowhai), Cordyline australis (cabbage-tree), Phyllocladus trichomanoides (tanekaha), Dacrydium cupressinum (rimu), Podocarpus spicatus (matai), Podocarpus dacrydioides (kahikatea), Podocarpus totara (totara). •

It may appear to many readers that numerous trees and shrubs have been omitted from these lists, but those enumerated have all been grown at Ruakura with satisfactory results. NOT RECOMMENDED FOR RUAKURA CONDITIONS. The following trees and shrubs cannot be recommended for planting on land and in' positions similar to those at Ruakura : (i.) Attacked severely by pests and diseases : Pinus halepensis (Aleppo pine), Pinus Sylvestris (Scots pine), Picea excelsa, Picea Menziesii, Cryptomeria elegans, Pittosporum eugenioides, Pittosporum crassifolium, Olearia Fosterii, Olearia Traversii, Viburnum Tinus (laurestinus) i (2.) Killed or badly affected by frost: Vitex littoralis (puriri), Corynocarpus laevigatus (karaka), Meryta Sinclairii (puka), Tecoma capensis.

Eleven years old. Note the overhanging growth, affording shade as well as shelter. SOME SPECIAL POINTS. Attention may here be called to a few special points of interest in connection with the Ruakura plantings. It will be noticed that Cupressus Lawsoniana takes first place as an all-round ornamental and shelter tree. If allowed to grow unchecked it forms a high and beautiful tree, affording excellent shelter right to the ground, as shown in Fig. 1. If planted closer together in a single row and clipped once a year it forms an excellent dense wind-proof hedge (Fig. 2). The tree is easily raised from seed, readily transplanted, hardy and vigorous, fairly quick-growing, will succeed in a great variety of soils and situations, is practically free from pests and diseases, and is not palatable to live-stock. It has therefore many good qualities to commend it. - . A splendid hedge of Cupressus Benthamii, eleven years old, is seen in Fig. 3. This variety of cypress had made heavier top growth than

Lawsoniana, and at a height of 9 ft. the branches overhang the protecting fences., thus affording valuable shade as well as shelter to live-stock. - ' . Cupressus macrocarpa is omitted from the list of trees suitable for' a high single-row shelter hedge. It must be admitted that in many instances it has been' planted as a single-line hedge, but in most cases ■the results have been unsatisfactory.. : Such hedges are full of gaps, as trees of. this species die out, not only when young, but at all stages of growth. Large heavy spreading branches are produced when the trees are planted in single lines, and, although useful for shade, bottom growth disappears as the trees grow old, and the value as a • .shelter hedge is lost.' When planted for timber* in blocks or wide belt's the trees grow straight, producing useful trunks and few side branches. Cryptomeria elegans is omitted as- a shelter-tree, mainly on account of the lower branches dying and failing to give bottom shelter to a hedge or belt; it also harbours numerous pests and diseases. Under the heading of a low single-row hedge it. will be noted that barberry- and Eleagnus mixed,is recommended. When planted together in this manner it is found that a more even and dense hedge is formed than with one of barberry alone ; and with the addition of barberry to. the Eleagnus live-stock leave the hedge alone. Eleagnus has been omitted from the list of garden or section hedges, for in such positions it requires constant clipping and demands too much attention. It also harbours numerous garden pests and diseases. Special reference is merited by -Pseudo-tsuga' Douglasii (Oregon pine). This tree has succeeded well at Ruakura in single-row hedges, in •combination with poplars for a high breakwind, in deep plantations, and as a single specimen tree in the open. It is a tree which can be easily propagated and readily transplanted. The young trees produce masses of fibrous roots, and when properly wrenched they lift with •excellent root-development. If planted with care and given a little -attention the young trees will make rapid growth, and when once firmly established, will soon form an excellent breakwind. POINTS FOR INTENDING PLANTERS. ' ' . To inexperienced settlers intending to plant, this first and important advice is offered : - (1) Select trees that will succeed in the class -of soil and situation when planted ; (2) select trees most suitable for the purpose for which they are to be planted ; (3) select well-grown and well-rooted trees from nursery establishments when purchasing. Remember that it is useless to plant a tender tree in an exposed -position, a high-growing tree where only a shrub is required, or a slow.growing timber-tree when quick shelter is desired,' and 7 a complete waste of time to plant poorly rooted and badly raised trees. On the other hand, many excellent trees never thrive because they are badly planted -and, when planted, completely neglected. It is,. of course, possible to group trees in order to combine ornament with shelter and shelter with timber. In most cases, however, when timber is the main object it, will pay to confine the planting tc timber alone, for in order to secure the best results in this direction -trees of one class must be kept together and planted in deep breaks.

It is better, therefore, to plant waste corners or unploughable areas on a farm with timber-trees rather than endeavour to intersperse them in the hedges and smaller shelter-belts on the farm. : In some cases , the lay-out of the farm may allow of the planting of a heavy break of timber-trees along the boundary-fence against the prevailing wind, and this will provide excellent shelter as well. conclusion. ' The value of ornamental and useful shelter hedges and trees round a homestead and on the farm cannot be overestimated. Beauty and use go hand-in-hand more frequently than we think, and the planting of trees will not involve a great increase in the cost of home-making. The cutting-out of so much native forest, particularly in the North Island, must have a marked influence over, the country, and it is essential that more trees be planted. Without shelter it is impossible to bring in much of our waste and wind-swept areas. No better demonstration could be given-than that • afforded by the Ruakura Farm. The 938 acres of original waste land, adjoining an area of 25,000 acres of open untouched swamp land, could not have reached its present high state of cultivation, with its excellent' pastures carrying large herds of thriving sheep and cattle, had not shelter-trees' been planted in the first instance. Combined with shelter is the beauty which these trees lend to the surroundings, and visitors from all parts of the world express delight at the beautiful lines of trees and hedges to be seen at this station.