4 MASS. EXPERIMENT STATION BULLETIN 324 



Soils derived from coarse conglomerate or pudding-stone are found principally 

 in Norfolk and Bristol Counties where they are classed in the Coloma Series. 

 Sandstone soils are limited to the Connecticut Valley, where Chicopee Soils on 

 the plains and Cheshire Soils on the uplands include most of the acreage on such 

 glacial drift. 



Limestone influences about 240,000 acres of soil, of which 45,000 acres are in 

 Franklin County and the major amount in Berkshire County. The Dover Series 

 is derived from limestone drift. Several other series are formed from gneissic or 

 schistose drift in which more or less limestone was intermingled by glacial action. 



The chemical composition of the weathered soil is similar to that of the under- 

 lying drift, which in turn must be related to the rocks from which the drift was 

 formed. These crystalline minerals, quartz, feldspar, and mica, make up much 

 of the granite, gneiss, schist, slate, and sandstone of the glacial debris. Orthoclase 

 feldspar and muscovite mica are both potash minerals. Dana states that the 

 former contains 16 percent and the latter 9 percent of potash. Quartz does not 

 contain potash. 



While each crystalline mineral has its characteristic composition, rocks like 

 granite from different localities differ in the proportion of each kind of crystals 

 and may vary in the percentages of potash to be found. Feldspar is the dominant 

 mineral in granite, while mica is most prominent in gneiss, schist and slate. Leith 

 and Mead, in "Metamorphic Geology," state that granite contains an average of 

 4.1 percent of potash. The micaceous rocks average less. Quartz prevails in 

 sandstones, but the coarse pebbles are usually of granitic character and sand- 

 stones are not barren of potash. Limestone is usually associated with other rocks 

 like schist or gneiss. Although it does not contain potash, the weathering of lime- 

 stone in glacial drift dissolves the limestone faster than it does the harder rocks 

 which contain potash. 



Effects of Potash in Fertilizer Experiments 



Fertilizer experiments at the Massachusetts Agricultural College were begun 

 soon after it was founded. From these experiments together with observations 

 of farm practice, Stockbridge in 1876 published several formulas for fertilizers 

 based on the chemical composition of the crops and their probable yields per 

 acre. For example, a crop of 50 bushels per acre of corn might contain 64 pounds 

 of nitrogen, 31 pounds of phosphoric acid, and 77 pounds of potash. To replace 

 this fertility, the corn formula called for 320 pounds sulfate of ammonia, 248 

 pounds superphosphate, and 154 pounds muriate of potash. 



Stockbridge's formulas were vigorously criticized by Director Johnson of the 

 Connecticut Agricultural Experiment Station as uneconomical and therefore not 

 practical. The large proportion of nitrogen was found to be uneconomical and 

 was lessened without any reduction in effects. Goessmann's experiments, begun 

 in 1883, finally settled in 1889 to the following quantities per acre: 45 pounds 

 of nitrogen, 80 pounds of available phosphoric acid and 125 pounds of potash. 

 By this time it had become generally known that nitrogen from the air was being 

 fixed by bacteria which grew on roots of leguminous plants. 



Soon after the establishment of the Office of Experiment Stations under the 

 Hatch Act in 1888, its director, Dr. \V. O. Atwater, suggested to the agricultural 

 experiment stations of the separate states that fertilizer experiments should be 

 conducted on different farms in order to show farmers what their soils most 

 needed of the various kinds of fertilizers. He called a conference of experiment 

 station representatives to formulate a plan of uniform fertilizer experiments, 



