Barn and Field Experiments in 1917. 17 



SOIL TEST EXPERIMENT AT AROOSTOOK FARM. 



Aroostook County, and particularly the part along the 

 Aroostook River, has two characteristic soils that are used for 

 cropping. These grade more or less from one into the other 

 but nevertheless they are 2 well marked types. The best 

 and most abundant potato soil, which occurs where the hard 

 wood growth flourished, has been named by the United States 

 Department of Agriculture's Bureau of Soils as "Caribou Loam. 

 This by imperceptable gradations shades off into a dark brown 

 or gray soil where the land was originally covered with black 

 growth (conifers). To this soil the name Washburn loam was 

 given. The principal soil type is the well drained "Caribou 

 loam." This is the great potato soil of Aroostook County. 

 Interspersing this is the poorly drained inferior "Washburn 

 loam." Originally these soils were similar in origin, but through 

 the centuries of plant occupation they have become biologically 

 different. — ,.; , 



One of the fundamental things in field agriculture is a 

 knowledge of the soil that is being worked with. Much has 

 been learned of Caribou loam from the experience of the men 

 who have been cultivating it for a generation. Chemistry, soil 

 physics, soil bacteriology and a study of the fungous organisms 

 also contribute to the knowledge of this soil. But important 

 as these sciences are they chiefly serve to explain results ob- 

 tained. There is one way — and only one way — to adequately 

 test a soil and learn its fertilizer needs. And that is by growing 

 the plants to be studied in the soil. 



After careful consideration of the difficulties and the ex- 

 pense involved the Station Council decided that all things con- 

 sidered there was no one thing that could be undertaken on 

 Aroostook Farm better calculated to add to the knowledge of 

 the permanent agriculture of the County than a long term experi- 

 ment with fertilizers. The crops and the soil type were easily 

 decided upon. Potatoes, oats and clover are now and are likely 

 to be for many years to come the 3 standing staple crops of the 

 county. And Caribou loam is the best and most common type: 

 of soil of the countv. 



