THE HORTICULTURAL SOCIETY OF NEW YORK 



grasses; and also, where they may have a sufficient quantity of sand to 

 make a clay loam that will provide for the prompt drainage of w^ater, the 

 best requirements of roses are met. 



On the other hand, a soil made up of sand particles, with sufficient of 

 the clay or fine particles to hold or bind them somewhat together, is most 

 excellent for very early blooming plants, for strawberries, and for early 

 vegetables. 



These sandy soil types are found along the coastal plains, the Atlantic 

 coast and the shores of lakes, and from these the early supplies of vege- 

 table foods come to meet the requirements of our cities. The heavier or 

 clay types, with their many variations, extend over wide areas and these 

 are adapted to the great agricultural or cereal food productions. On these 

 stronger soils will be found our largest and most beautiful trees, those 

 reaching to magnificent dimensions, while on the sandy types trees are 

 more diminutive in size, both plant food and moisture on such soils being 

 less stable and regular in supplying the needs of the trees. 



In the month of June, when the temperature of the atmosphere is high, 

 an acre of grass growing on a lawn or in a meadow requires an immense 

 quantity of water to meet its demands, and this has been computed, through 

 the careful measurements that have been made of the transpiration of 

 moisture through the many plants, as one hundred tons daily per acre, 

 through the bright sunny days of June, and on all days with a prevailing 

 north wind. 



It has also been ascertained that a full grown elm tree, carrying a strong, 

 unimpaired foliage, will take up on such days, and pass off into the atmos- 

 phere, six and one half tons of water. 



To obtain one ton of dry matter in corn, oats and wheat, all important 

 food-producing plants, the soil must yield up from two hundred and forty 

 to five hundred and fifty tons of water for each ton of dry matter formed, 

 and when this very important relationship that exists between the soil and 

 plant life and the further relation they hold to human life are better 

 understood, a greater knowledge of these principles and facts becomes 

 paramount. 



With an annual average rainfall of but about forty-four inches for New 

 York and the New England States, the question naturally arises, from 

 what source do plants obtain such enormous quantities of water, particu- 

 larly when the distribution of the rainfall is so uneven, that practically 

 for weeks in succession, and through the most active season of growth, 

 no rain falls on the earth, and protracted droughts are experienced. It 

 is from the great subterranean supplies of water that are stored in the 

 earth, upon which plants may draw in times of need, that their existence 

 and continued growth become possible through such periods. By the rapid 

 evaporation that goes on through a high temperature over the surface, 

 an active, upward movement of the subsoil water sets in to supply that 

 lost by surface evaporation, and at the same time the roots of plants, 

 not getting the ready supply they require, are forced to go down deeper 



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