THE HORTICULTURAL SOCIETY OF NEW YORK 



The improvement of the soil then becomes of first importance. This 

 may be done by a more thorough system of tillage. Better mechanical 

 condition and more refinement of the soil will make the plant-food it 

 contains more readily available. 



The incorporation of vegetable matter through manures and by the use 

 of leguminous plants, grown and ploughed in, is one of the most essential 

 needs for the resupplying of the humus, much of which has become worn 

 out and exhausted by long years of production. The use of clover for 

 this purpose is most valuable. Its long roots go down deep, penetrating 

 the subsoil, opening it up to the more active operation of the oxygen of 

 the air, admitting more of warmth and adding to its capacity to hold more, 

 and over a longer period, the moisture necessary for the needs of plants. 

 Clover has the added important function of being able to utilize the 

 nitrogen of the air, and, in cooperation with certain soil bacteria, to build 

 up abundantly in the soil this essential and most costly plant food. The 

 application of lime at times will be beneficial to practically all soils for its 

 corrective influence on the deleterious bacteria that are more or less present 

 in them, and which frequently retard the best development of plant life. 



The soil is usually looked upon as so much dead, inert matter, when the 

 fact is it is full of life and activity. Its every atom is in constant motion, 

 through friction caused by the powerful rays of the sun that are steadily 

 beating upon the surface of the earth. It is constantly undergoing changes, 

 by the building up as well as the breaking down processes that are going 

 on through the agencies of air, water, heat, cold and plants. 



The world owes much to an early investigator, thinker and discoverer, 

 in Jethro Tull, an English agriculturist, born in 1674, who published "The 

 New Horse Hoeing Husbandry " or " An Essay on the Principles of Till- 

 age and Vegetation." 



He may be termed^ the first preacher of the gospel of tillage. After 

 actual experiments had been carried on in the field, and he had obtained 

 positive results in the improvement of the soil and marked increase in 

 yields through tillage alone, in his reasoning upon the effect of tillage 

 he believed that the soil was the sole basis of support for plants and that 

 plants took up small particles of it in their growth, and that the finer the 

 particles were made through tillage the more readily plants could utilize 

 them as food ; hence the famous statement which he made and which has 

 since been much discussed that " tillage was manure." 



While Tull was mistaken in his belief that plants took up their food in 

 small soil particles, nevertheless he did great good in starting Hnes of 

 investigation and practices in the tillage of the soil out of which vast good 

 has grown. 



Soils differ largely in their composition and these differences need to 

 be understood in their effect upon plants. A heavy soil, made up largely 

 of fine particles, so fine as to be classified as a clay, is well suited to 

 certain plants, those that require a large amount of moisture and a cooler 

 degree of temperature. This type of soil is particularly adapted to 



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