FIKLD CROPS. 4-il 



barnyanl inamire jmived iiiucli less effective than commercial fertilizers. Kainit, in 

 the alis('n((> of barnyard manure, greatly benefited the crop?, especially the oat crop. 

 In general, applying all the commercial fertilizers to the root crop proved to be a 

 better i)ra(ti((' tlian using a certain portion for each cro]> in the rotation. 



Suggestions for the manuring of various crops {Ecading Col., Afjr. Tkpl. Rpt. 

 1900, ]>j). 44-4^ )■ — Brief notes on the manuring of peas, l)eans, swedes, turnips, rape, 

 mangels, potatoes, cabbage, cereals, rye grass, clover, and meadoAV and pasture lands. 



Tlie importance of the selection of varieties in plant culture, Edlek [Hes- 

 sische Ldiuhr. XtscJn:, 71 {IMl), Xo. 0, pp. SS,6'9). 



The utilization of the agave plant in Mexico {Milt. Dent. Lotidir. dixelL, 16 

 [1901), Sup. to Xo.^. 7, pp. .Jl, 52; .V, pp. 55, 56). 



The production of barley for brewing purposes, von RIimker {Fiildhig'.'i 

 Landv. Zt<j., 50 (1901), Nos. 2, pp. 53-58; 3, pp. 95-104). — A paper discussing the 

 profits in the cidture of the crop and the requisite quality of barley for brewing pur- 

 poses. Special attention is given to the use of fertilizers. 



The influence of the fertilizers application and the water content of the 

 soil upon the form and composition of the barley plant, von Seelhorst and N. 

 GfiOKtis {.Tour. Landir., 4S {1900), Xo. 4, pp. 325-347). — This work includes studies 

 of the influence of plant food and soil humiditj' on the relation of root development 

 to the rest of the plant, on the development of the parts of the plant above ground, 

 on the total yield of straw and grain, and on the yield of grain alone. The plants 

 were grown in pots containing 20 kg. of soil, which was fertilized with quantities of 

 potassium carbonate, sodium nitrate, and monocalcic phosphate furnishing 1 gm. 

 of potash, nitrogen, and phosphatic acid, respectively. These fertilizers were applied 

 in different coni})inations. drains of barley of uniform weight were sown March 28. 

 The soil of all the pots was kept equally moist at first to insure unifonn germination. 

 April 20 the water content of the soil Avas differentiated and the pots divided into 

 three series, namely, the first series with a low water content of 49 per cent of the 

 water-holding capacity of the soil, the second series with a medium water content of 

 62 per cent, and the third series with a high soil humidity of 76 per cent of the 

 water required to saturate the soil. The results were similar to results obtained in 

 this kind of work with oats. (E. S. R., 13, p. 125.) The conclusion is that supply- 

 ing tlio element or elements of plant food which are present in the soil in only min- 

 imum (juantities, favors the develojiment of the roots as well as the parts of the plant 

 above ground, and that the increase of organic substance in the soil due to the devel- 

 opment of the roots has a l)eneficial effect on the succeeding crop. It was noticed 

 that the low water content of the soil induced a greater development of the root sys- 

 tem, and attention is called to the fact that an increase in root development means a 

 withdrawal of plant food from the other parts of the plant. The application of nitrog- 

 enous fertilizers when only a small amount of nitrogen was present in the soil, 

 together with a iiigh soil humidity, favorably influenced the stooling of the plants. 

 The increase in the number of the internodes due to a higher water content was not 

 quite regular, Init nevertheless (juite perceptible. The influence of fertilization in 

 this respect was less evident. In every case where the humidity of the soil was 

 increased without the application of nitrogen the strength of the culm decreased, 

 while under the same conditions with the use of nitrogen in the fertilizer the strength 

 of tiie culm increased. Increasing tlie soil humidity and furnishing nitrogen in the 

 plant food increased the length of the culms and of the different internodes, the 

 incn-ase being greatest in the 2 upper internodes. The length of the third, fourth, 

 filtli, and sixth internodes agreed with the length of these parts as laid down by 

 Nowacki's law, but this was never so in the ca.se of the second internode from above. 

 The length of tiie heads and the strength of the culm were effected by the same 

 factors. The increa,«e of soil humidity with no nitrogen shortened the heads, while 

 witii the use of nitrf)gen the increase in the water content of the soil lengthened 



13639— No. 5 4 



