40 EXPERIMENT STATION RECORD. 



indicate that a difference in the ability of plants to resist acidity exists, and that in 

 this experiment Mammoth Red Clover grew better on acid soil than medium red 

 clover. 



The effect of a lack of potash on clover and timothy, II . vox Feilitzen 

 (Svenska MosskuUurfor. Tidskr., 17 {1903), No. 5, pp. 365-368; 18 (1904), Nos. 1, pp. 

 33-44; ■■,]>!>■ 96, 97). — A brief description is given of experiments with a so-called 

 potash fertilizer which was found to consist of ground feldspar. If the increase in 

 yield of green substance on the plat receiving 100 kg. potash in 37 per cent potash 

 salt be placed at 100, the same amount of potash in the fertilizer gave a yield of 7, 

 and twice this amount, a yield of 43. The plants grown on the unfertilized plats or 

 upon those receiving applications of ground feldspar developed very slowly and 

 made a weak growth; a great many yellowish-green specks appeared on the leaves, 

 indicating a partial destruction of the chlorophyll, very likely due to the absence of 

 soluble compounds of potash. Colored and other reproductions of the appearance 

 of the plants at the time of harvesting accompany the report. 



The analyses made of the hay harvested on the different plats showed that the 

 potash content of the hay grown on the unfertilized or ground feldspar plats ranged 

 from 0.600 to 0.635 per cent, while that grown on the plats receiving 37 per cent 

 potash salt contained 1.105 per cent. On these same plats the soda content of the 

 hay ranged from 0.140 to 0.245 per cent, as against 0.020 per cent on the potash plats, 

 showing a relation of potash to soda as 100 : 23 to 39 in one case, and in the other as 

 100:2. If the amounts of potash applied on the different plats be compared with 

 those contained in the harvested crop, it is shown that only 4.8 to 8.6 percent of the 

 potash in the feldspar was utilized by the crop, while in the case of the potash 

 fertilizer 92.8 per cent reappeared in the crop harvested. — f. w. woi.l. 



Selecting and preparing seed corn, P. G. Holden (Iowa Sta. Bui. 77, pp. 169- 

 234, figs. 47). — This bulletin gives directions for the production, storing, and pur- 

 chase i if seed corn; reports results of experiments with corn at the station, and points 

 out at some length, by means of illustrations and discussions, the characteristics to be 

 sought in the selection of kernels, ears, and plants. The following points are con- 

 sidered: Form, size, and type of kernels, shape and size of ears, position and arrange- 

 ment of kernels on the cob, proportion of corn to cob, barren plants, uniformity in 

 the height of ears upon the stalk, pollination and germination. 



The productivity of different ears of corn was compared by planting the most per- 

 fect kernels from 102 of the best ears. The records show that there was a variation 

 between the individual ears in yield from 36.06 bu. to 90.56 bu. per acre, in stand 

 from 43 per cent to 96.5 per cent, in broken stalks from 41 to 258 or from 8 per cent 

 to 64 per cent, in barren stalks from 6 to 79 or from 1.5 per cent to 21.5 per cent, and 

 in the number of suckers from to 106 or 21 per cent. These extremes in all cases 

 showed a marked difference in the yield. The 10 best ears averaged 83.71 bu. per 

 acre and the 5 poorest 40.05 bu., while the entire series of 102 ears gave an average 

 yield of 67.09 bu. 



Records of corn planter tests presented show that the edge drop planters gave 

 much better results in the number of times 3 kernels were dropped in dropping 500 

 hills than the planters provided with the common round hole plates. 



In a shrinkage experiment begun October 24, the corn under test had lost 12.60 

 per cent in weight by February 27. Rates of shrinkage were also determined for 7 

 different varieties. Nashes Early Yellow, which was perfectly matured when the 

 test was begun October 31, showed a shrinkage of 4.93 per cent on January 9, while 

 in unmatured Reid, the loss in weight for the same period amounted to 17.49 per 

 cent. The shrinkage in 4 leading varieties of field corn, for 9 months after husking 

 and cribbing, is shown in the following table: 



