FIELD CROPS. 743 



Where no grain was produced the stalks and leaves contained large 

 amounts of nitrogenous matter. — p. fireman. 



Soil inoculation for leguminous plants, J. F. Duggar (Alabama 

 College Sta. J: id. 87, pp. 459-488, figs. 12). — Inoculation experiments with 

 a number of legumes were conducted on various soils in the field and 

 the greenhouse. A discussion of nitrogen -collecting plants, the func- 

 tion of root tubercles, methods of soil inoculation, and the value of 

 winter- growing legumes is given. 



October 17, 1890, 1 fortieth-acre plats were sown with seed of hairy 

 vetch. The .soil was very poor, but was fertilized at the rate of 400 lbs. 

 per acre of acid phosphate and 120 lbs. per acre of sulphate of potash, 

 no nitrogen being applied. Two of the plats were inoculated. "The 

 seed was dipped in water in which there had been stirred and allowed 

 to settle earth from a lawn once a garden spot where common vetch 

 ( Vicia sativa ) had for several years in succession made a thrifty growth." 

 All plats were cut May 20, 1897. The yields of only 2 plats are given — 

 the uninoculated plat yielded per acre 900 lbs. of green forage, which 

 made 232 lbs. of cured hay, and the inoculated plat produced 9,13G lbs. 

 of green forage per acre giving 2,510 lbs. of cured hay. The soil of the 

 inoculated plat was left in a better mechanical condition than the soil 

 of the other plat. 



Pot experiments were made in the greenhouse with hairy vetch, 

 Canada field peas, crimson clover, alfalfa, white lupine, lespedeza, and 

 cowpeas. The soil for these experiments was taken from an upland 

 rocky cotton field which had been cleared about 20 years, a sandy cot- 

 ton field cleared about 5 years, a woodland, a lespedeza pasture, and a 

 cowpea field. Special germ fertilizers were used for inoculation in some 

 of the experiments, but the inoculating material for cowpeas consisted 

 of soil taken from around old cowpea roots, and that for lespedeza of 

 soil from the lespedeza pasture. Hairy vetch and crimson clover were 

 inoculated with clover Mtragin, Canada field peas with vetch Nitragin, 

 and white lupines with lupine Nitragin. Alfalfa was inoculated with 

 dust from the seed of bur clover (Medicago maculata). The organisms 

 adhering to the perfectly dry bur clover seed had retained their vitality 

 from the time of harvesting in May or June until late in the following 

 October. The cost of inoculating with Nitragin is estimated at $2.20 per 

 acre. The results of all the experiments are tabulated in an appendix. 



Among others, the author makes the following summaries : 



"Inoculation with the germ fertilizer or Nitragin greatly increased the yields of 

 all these plants as compared with untreated plants. This increase in the weight of 

 inorulated plants, after thorough drying, was as follows: Hairy vetch, 89 per cent; 

 Canada held peas, 138 per cent; crimson clover (young plants), 146 per cent. Germ 

 fertilizer prepared for vetch was effective on Canada field peas. Inoculation mate- 

 rial procured without cash outlay acted like Nitragin and greatly increased the 

 yields of hairy vetch and alfalfa. 



"Soil from a field where a given leguminous plant has recently been successfully 

 grown is an effective inoculating material for the same kind of plant when first 

 sown in a soil not already naturally supplied with the required form of germ life. 

 13777— Xo. 8 1 



