FIELD CROPS. 635 



each instance representing equal amounts of nitrogen. A definite 

 portion of the southern end of each plat, except the control plat, was 

 limed in 1893 at the rate of 2^ tons of air-slaked lime per acre. The 

 north end of 3 plats received in addition lime at the rate of 5 tons per 

 acre in 1891, and in 1892 an additional amount equivalent to 3.3 tons 

 per acre. Indian corn, oats, clover, and barley were grown on the 

 plats up to the fall of 1897, when they were seeded down with a mix- 

 ture of 15 lbs. each of meadow-oat grass, awnless brome grass {Bro- 

 iiius iner)iiis)^ Kentuck}' blue grass, and orchard grass. The Ken- 

 tucky blue grass failed to germinate. The yield of green material 

 obtained on the limed and unlimed sections of the different plats for 

 each of the years 1897 and 1898 are tabulated. The herbage on defi- 

 nite areas of the limed und unlimed portions of each plat was sorted, 

 weighed, and photographed. 



In 1897 the average yield of green material on the limed portions of 

 the plats was at the rate of 6.72 tons per acre, and on the unlimed 

 portions 3.86 tons per acre, a gain of about 7-1: per cent b}' liming. 

 In 1898 the average yields on the limed and unlimed sections were at 

 the rate of 5.02 and 1.96 tons per acre, respectively, a gain of 156.1 

 per cent b}- liming. Considerable variation in yield occurred on the 

 differently fertilized plats. The largest 3-ield of green material in 

 both 3^ears was obtained on the limed plats fertilized with a full 

 ration of nitrate of soda (-180 lbs. per acre), followed by full rations 

 of sulphate of ammonia and dried blood. Considei'able green mate- 

 rial in each instance was grown on the unlimed portions of these plats. 

 In the case of the nitrate of soda plat, this consisted mostlv of grass, 

 while with sulphate of ammonia, sorrel was the chief constituent. 

 The especially good showing as regards vields of grass of the unlimed 

 section of the nitrate of soda plats is thought to be due to the gradual 

 neutralization of the soil acidity by years of continuous application of 

 this fertilizer. 



As regards the growth of weeds on the different plats, the percent- 

 ages on the limed section in 1897 ranged from 8.1 to 28.9, though in 

 only one case did it exceed 18.3. On the unlimed sections the per- 

 centages ranged from 3.5 to 99.1, and in 3 instances it equaled or 

 exceeded 81.8. The bulk of the weeds on the unlimed section was 

 made up of sorrel. 



The weights and percentages of each species of herbage found on 

 the different plats in 1898 is shown in tabular form. With orchard 

 grass and awnless brome grass marked increase in yield regularly 

 resulted from liming. Meadow oat grass was helped some by liming, 

 but was less dependent on its presence than either orchard grass or 

 awnless brome grass. Timoth^^ w^as not sown on the plats, but 

 appeared in nearly every instance on the limed sections and but twice 

 on the unlimed sections, indicating the value of neutral or slightly 



