On this plantation much has been done toward the improvement of this 

 type with a large measure of success, and there is no reason why yields 

 of as much as 1 bale of cotton, 40 bushels of corn, and 50 bushels of 

 oats per acre should not be secured generally throughout the county by 

 proper treatment. The soil is perhaps better adapted naturally to the 

 production of oats than to any other crop commonly grown here. 



RESULTS OF DIFFERENT MANUR1AL TREATMENTS OF PORTSMOUTH 



SANDY LOAM. 



The soil used in this test was a composite sample of about 500 

 pounds. It was taken to a depth of 7 inches, which is the present 

 depth of cultivation, and was considered thoroughly typical of this soil. 

 An acre from which this sample was secured was reserved for use in 

 field demonstration of such treatments as might give very beneficial 

 results. 



The method consists in growing wheat for a period of twenty to tWenty- 

 five daj T s in small wire baskets, which, after being filled with soil and 

 planted with wheat, are sealed with paraffin, so that practically no 

 moisture is lost from the soil except through the transpiration of the 

 wheat. By periodically weighing the baskets and adding distilled 

 water from time to time a favorable moisture content of the soil is 

 maintained. At the close of the experiment the plants are cut and 

 weighed, so that both the green weight of plants and the water used in 

 [the course of growth are ascertained for each treatment. Under the 

 conditions of the test the draft made upon the soil by the plants, even 

 for so short a period, is greater than that which occurs in the field 

 during the full growing season. 1 



Iri the first test of this soil 20 manures and fertilizers, or combinations 

 thereof, were given in comparison with the untreated soil, there being 5 

 baskets for each 'treatment. The table on the following page gives the 

 treatments for those which produced a marked increase in growth, 

 together with the comparative weights of the plants, those from the 

 untreated soil being taken at 100. 



1 For fuller description of the method see Circular No. 15, Bureau of Soils, U. S. 

 Dept. of Agr. 



