4 BULLETIN 998, U. S. DEPARTMENT OF AGRICULTURE. 



the degree of injury occurring in this section as well as curtailment 

 of yield would be of greater practical significance than in sections 1 

 and 3. The accompanying illustrations 3 show very well the type and 

 degree of injury found, especially the effect of applying small quan- 

 tities of borax. (PI. I.) As the quantity of borax increased there 

 was a marked falling off in the number of plants on a plat (PI. II) 

 as well as a reduction in the size of the plants (PI. Ill, Figs. 1 and 

 2, compared with a normal plant in Fig. 3). A great many appar- 

 ently empty hills when dug into disclosed seed pieces affected to the 

 extent shown in Plate IV, Figure 1. The greatest degree of injury 

 resulted from the use of the larger quantities of borax, namely, 100, 

 200, and 400 pounds per acre (PI. IV, Fig. 2). 



During the investigational survey in Maine in 1919 the quantity 

 of anhydrous borax found in commercial fertilizers collected ranged 

 from 0.73 to 2.3 per cent. In view of the fact that 2.000 pounds 

 represents the usual quantity of fertilizer applied per acre, it is 

 evident that the borax applied ranged from 14.6 to 46 pounds. The 

 type of field injury shown in 1919 was similar to that found with 

 the 20, 30, and 50 pound applications in the borax experiment of 

 1920, thereby serving to substantiate the previous findings. Some 

 of the injurious effects noted in both seasons were as follows. (1) 

 Failure of seed to germinate; (2) dying back of underground 

 sprouts; (3) bleaching of foliage, or, if the plant was not seriously 

 injured, a marginal yellowing of the leaflets; (4) reduction in size 

 of plants below normal; and (5) a reduction in yield. 



On September 9, the plats were harvested and the weights of the 

 potatoes, by plats for the three sections, were recorded (Table 1). 

 The results are presented graphically in Figure 1. 



In section 1, where borax was applied in the furrow, injury occurred 

 from the 10-pound application of borax and became progressively 

 worse. It will be noted, however, that the degree of injury was less 

 than in section 2, where the borax was applied in the furrow and 

 planting was done immediate^. The application of 1, 2, and 3 

 pounds of borax per acre apparently stimulated plant growth, and the 

 yields were increased. 



In section 2 the injury was apparently produced with as small 

 quantities of borax as 3 or 4 pounds per acre, certainly with 5 pounds ; 

 and the injury with 10 pounds and more was great. 



One of the significant features of section 2 is the effect shown on 

 the yield by the 10, 20, 30, and 50 pound applications of borax, as 

 this was practically the range found during the investigational sur- 

 vey made in 1919. 



3 The writer is indebted to Dr. C. F. Clark, of the Office of Horticultural and Pomo- 

 logical Investigations for his cooperation in obtaining photographic records. 



