No. 7. DEPARTMENT OF AGRICULTURE. . ?97 



gen in forms available to growing plants. Nitrogen costs eighteen 

 cents a pound in commercial fertilizers. At that price we must de- 

 pend upon the air for at least a part of the supply for the growth of 

 crops. It is equally true that a rotation of crops is essential in 

 order to prevent the increase of fungous diseases and insect enemies 

 to a point where the crops are seriously injured or even completely 

 destroyed. 



The soil on which this series of experiments is being conducted is 

 especially favorable to the best use of plant food. The soil is a silt 

 or clay loam of limestone origin, belonging to that series of soils to 

 which soil experts have given the name of Hagerstown. The heavy 

 soils in the limestone valleys of southeastern Pennsylvania are iden- 

 tical in origin and character to the soil on which these experiments 

 were made. 



The natural drainage on the experiment station farm is almost 

 perfect. In digging a well at the college water was struck at 150 

 feet and a satisfactory supply obtained at 385 feet below the surface. 

 The land has been underlaid by heavy beds of limestone. The grad- 

 ual dissolving of this limestone material has left underground chan- 

 nels, thus making a ready escape for the surplus water, while the 

 heavy nature of the soil and subsoil cause them to retain sufficient 

 water under existing climatic conditions for the growth of crops. 



Not infrequently soils fail to respond to fertilization or cultural 

 methods on account of the lack of lime. The soil and subsoil in the 

 blue grass roadways between the tiers of plats were analyzed during 

 the past year. The soil was found to contain approximately .5 of 

 one per cent, of lime and the subsoil .6 of one per cent. This is 

 something more than twice the amount of lime generally assumed 

 necessary for a good soil. In these experiments 4,000 pounds of 

 burned lime applied to the soil once in four years without any fer- 

 tilizer has during twenty-five years slightly decreased the yield, while 

 4,000 pounds of ground limestone applied every alternate year 

 slightly increased the yield. Where 4,000 pounds of quicklime was 

 applied once in four years to a plat which receives six tons of yard 

 manure every alternate year the yield was equal to that from the 

 plat receiving ten tons of yard manure without lime. In other 

 words, lime without manure decreased the yield, lime with manure 

 increased the yield. This is a lesson that every land owner should 

 learn. 



For over a third of a century the College has had the same farm 

 superintendent. When the lecturers of our college were babies, or 

 at least very yonng children, Mr. Patterson was associating his name 

 with that high type of farming to which we have given the name 

 "Patterson Farming,'' which means doing the right thing at the 

 right time. The methods of cultivation, seeding and harvesting 

 have been under his immediate care during the whole of the experi- 

 ment. It is needless to say that all operations have been performed 

 as uniformly as i)ossible for all plats, in order that any variation 

 of yield might not be due to differences in cultivation, seeding or 

 harvesting. 



As before stated, each year a complete rotation of crops is grown 

 on the four tiers. Fertilizers are applied on alternate years, namely, 

 to the corn and wheat. No fertilizer has ever been applied to the 

 oats or the grass, any increase in yield in these crops being due to 



