6 MARCH 1976, Page 16

Tree uses

Denis Wood

The Tree Council was formed two years ago to focus attention on the importance of trees in both town and country and to remind local authorities, and indeed all of us, that the tree population is declining, a process made worse last year through casualties in gales, the ravages of Dutch elm disease and the failure of many newlyplanted saplings to survive in the dry summer because they were not watered. With Dame Sylvia Crowe as its chairman, the Tree Council must be able to give sensitive, educated advice on what trees to plant in particular places; and it is hoped that such advice will be freely drawn upon, particularly by the few remaining local authorities which have not progressed beyond the times when parks departments, motivated by well-meaning but intellectually half-baked council members, associated trees with the pretty colour and facile charm which they look for in their own 'lovely gardens'.

It must be some lingering of this mentality which is responsible for such 'pieces of street furniture' as trivial hanging baskets swinging in eerie irrelevance from lamp standards in cities and towns. How much better it would be if the thousands of pounds spent each year in providing bedding plants and keeping them watered were to be used to buy and plant trees to give scale and dignity to towns and streets. This matter of scale is important too in the choice of trees for different situations. A rough and ready rule might be that, to look to the top of a tree without craning one's neck, one should stand no closer than one and a half times the height of the tree, which represents an angle of about 35 degrees from one's feet on the ground to the top of a tree. Thus, to contemplate in comfort a tree 100 feet high one should stand 150 feet away—a distance considerably greater than the length of a full-size tennis court. A small garden of a quarter of an acre or less needs smaller trees—Rowans, Whitebeams, Thorns and such small exotics as Arbutus and Judas Trees. Larger gardens will accept taller 'domestic' trees—Robinias, Cataspas, Limes and Walnuts, which latter are too much neglected. In the wilder landscape we look for coppices and woods of Hazel, Alder, Birches, Beeches and Oaks.

The uses of trees are many. Economically they provide timber, and they form shelter belts to protect other plantations (such as orchards) and to prevent soil erosion. .Pictorially they are beautiful when seen at first hand in a landscape, whether in beech hangers on the chalk slopes, as groups of pines against the sky or as oak woods with their delicious under-flora of wood anemones, wild violets, primroses, woodruff and bluebells in the clearings. Philosophically trees are indispensable to our wellbeing because, for generations, they have set a vertical scale in which we are at home. We are happiest living in what some architects have called 'the tree scale', in which seventy to eighty feet implies a tall tree. A man may have the salutary experience of being put in his place when he stands under an eighty-foot beech, but he does not feel annihilated as he does when looking up at, say, the Vickers Tower at Millbank.

National Tree Week this year is from 6 to 14 March. For one who already knows what kind of tree he ought to be planting and only needs an outside stimulus to trigger him into action, trees can be planted in that week and probably in the north up to the end of March. Others will use this week for getting together information, building up a mental bibliography and going to see mature trees in botanic gardens and the Royal Horticultural Society's garden at Wisley, and reach a decision in time for planting in November.

There are many good books on trees, some effusive and highly coloured, but probably the most useful is Trees for Town and Country by Brenda Colvin, published by Lund Humphries. This has black and white photographs of sixty trees and also, for each one, line drawings showing the structure and outline and indicating the rate of growth. For example: English Oak, twenty-five feet in twenty"' eight years; White Willow, twenty-five feet in twelve years; Arbutus, fifteen feet in twenty-five years. Two other unpretentious books are The Identification of Trees and Shrubs by F. K. Makins, published bY Dent, and British Trees in Winter also by F. K. Makins and published by Dent. The 'bible' is still Trees and Shrubs in the British Isles by W. J. Bean, first published by Murray in three volumes and now beilig steadily revised into four volumes.