THE HORTICULTURAL SOCIETY OF NEW YORK 



into the subsoil, where the moisture supply is more abundant. This leads 

 then to a consideration of methods that shall in the most effective way con- 

 serve soil moistvire. Over-planting should be avoided. This will apply par- 

 ticularly to parks. Many parks are suffering at the present time over a wide 

 territory, from the effects of three successive years of protracted droughts. 

 The trees are showing weakness of foliage and little growth, while many 

 are failing and are in a decline from which they will not recover. 



These trees have planted around them shrubs that are in an equally 

 unsatisfactory condition and all are struggling for their daily water require- 

 ments which are not sufficient. Conservation of the w-ater is the urgent 

 need, and the only way to reach the case is to remove either the trees or 

 the shrubs that cannot be sustained by a too hmited water supply. 



The soil should contain not less than forty per cent, of moisture and 

 fifty would be better. By not planting so heavily as is generally done both 

 in public parks and on private grounds, very much better trees may be 

 had in their not being robbed of the water they require by the planting 

 of other things so closely about them. 



A second methed of conserving moisture is by incorporating a larger 

 amount of vegetable matter or humus in the soil. Where the character 

 of plants is such that the soil may be tilled or stirred, the working in of 

 green vegetation is excellent. For this purpose various plants may be 

 used, but those of the leguminous family have the highest value. The 

 clovers are especially good for this purpose. In their decomposition they 

 leave the soil in the best physical condition, while at the same time they 

 add one of the most costly of all plant foods, nitrogen, and at the least 

 possible cost. 



The seeds of crimson clover may be scattered about growing plants 

 quite late in the summer and allowed to grow through the autumn and 

 then turned in or left to protect the soil from the evaporation of its water 

 as a covering through the winter. While not so rapid as during the hot 

 weather, evaporation of soil moisture goes on during the winter, there- 

 fore it is desirable, so far as possible, to have the soil covered during the 

 winter with a living plant. The adding of vegetable matter, even if only 

 in a small quantity, will enable the soil to hold its water supply and dis- 

 tribute it over a much longer period of dry weather. 



Another method of conserving soil moisture is through the frequent 

 stirring of the surface of the soil. 



With the constant pressure of the water upwards to supply the loss that 

 takes place through evaporation, passages or channels are formed in the 

 soil and through these the soil moisture more readily reaches the surface. 

 The frequent stirring of the surface seals over these passages and the 

 moisture is thereby held for the greater use of the roots of the plants. 



Where field culture is carried on, any crops that may admit of fine culti- 

 vating implements being run over them may be successfully brought 

 through. Plants that show a famished condition with their foliage droop- 

 ing for the want of moisture, may be revived and kept in a flourishing 



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