544 MATE HORTICULTURAL SOCIETY. 



An impression prevails with novices in fruit-growing, and with some who 

 do not regard themselves as novices, that the quality of fruit may be im- 

 proved and its early ripening hastened by stripping the trees of a portion of 

 their leaves. This is a serious mistake, as any one who considers what the 

 functions of leaves are will readily understand. They are the lungs of 

 plants, and it is largely through leaves that plants receive their nutriment. 

 Strip a fruit-laden tree of any portion of its foliage and you cut off one of 

 the main sources of supply of food for the growing fruit. Not only so, but 

 the fruit draws on the store of substance and vitality laid up in the tree, and 

 thereby may be the cause of its ruin. Any one who has noticed the effect 

 produced on fruit when the leaves of a tree or bush are eaten off by worms 

 does not need to be reminded of the risk of leaf-pruning. Growth ceases, 

 there is a want of flavor, and immaturity generally. And what is true of 

 the effect caused by stripping a tree of its foliage is equally true of summer 

 pruning, unless it be^done on a very moderate scale. It is jDOSsible that by 

 pinching off the extremities of twigs more plant-food goes to nourish the 

 fruit, but the experiment is one that should be made with great caution. 

 The best pruning is that which is done before the leaf-buds unfold in early 

 spring, and before the sap has begun to How. 



Use of Leaf Hairs. — Dr. C. E. Bessey, of Nebraska, remarks that it is a 

 matter of common observation that the leaves of many plants are more or less 

 hairy. In amount it may range from the excessive wooliness of the familiar 

 mullein to the perfect smoothness of the lilac and cotton wood. Often the hairs 

 are confined to one surface alone, as in some of our apples and grapes. In 

 Iowa we have a wild plant, an artemesia, nearly related to the sage brush of 

 the far West, which starts out with its leaves entirely whitened with long silky 

 hair, but as the leaves grow older and rougher they lose the hairs from their 

 upper surfaces, but always retain them below. The common Concord grape 

 does much the same thing. Even a lilac leaf is more or less hairy when it first 

 appears. 



Now, why this hairiness? What office do these hairs perform? What good 

 purpose do they subserve? We do not need to go far for at least a partial 

 answer to this question. If we compare the plants of a moist region with those 

 from dry climates, we are at once struck by the remarkable hairiness of the 

 latter as contrasted with the former. And right here we get a strong hint at 

 the purpose of this hairy coat. It is evidently a protection against the exces- 

 sively dry air, which would otherwise dry up and destroy the leaf tissues. The 

 mullein leaf can endure the drouth of mid summer and autumn which would 

 utterly destroy plants not so well protected as these are. 



Here Are find, also, the explanation of the more common hairiness on the 

 lower surface. Of the two surfaces of the leaves the upper is generally by far 

 the better protected against excessive loss of moisture by an almost impervious 

 epidermis; the lower surface is almost invariably of a looser and softer texture, 

 and so is much more subject to injury from dry winds. The hairs on the lower 

 side of the leaves of some apples guard the delicate cells of that side, while the 

 cells of the upper surface are amply protected by an unusually thick and firm 

 epidermis. May we not wisely take the hint given us here, and when we select 

 trees and shrubs for dry climates give the preference to those which are most 

 woolly or hairy? 



