FIELD CROPS. 827 



of the crop, while the percentage of water in the soil remained the same. It 

 is {jointed out as most likely that the decrease in growth in the first instance 

 was dne in part to a lack of water-soluble nitrogen, and that the subsequent 

 increased growth was due tlirectly to the nitrogen applied ami that it served 

 :is plant food. The results are taken as suggesting that weeds by taking up 

 a portion of a small amount of nitrogen just at the critical period of the plant 

 which is being cultivated may cause the injury so commonly observed. 



A series of observations on alfalfa made at the Cornell Station (E. S. K.. IT, 

 II. 10.")9) and bearing on the subject under discussion are reviewed. "When 

 nitrate of soda is added to the soil, as repeatedly shown in the investigations 

 at this [CorftellJ station and eLsewhere. part of the nitrogen is fixed in the soil 

 and a i)art of it goes into solution. What prol)ably happens is that as the soil 

 is exhausted cf its water-soluble nitrogen by the paint, a part of this fixed 

 nitrogen goes into solution. The behavior of nitrate of soda when applied to 

 soils strongly indicates this action. What probably happens is, that when 

 nitrate of soda is applied more nitrogen keei)s going into solution, at just the 

 time when the plant is making great demands on the soil for this nitrogen, 

 than when nitrate of soda is not added." 



On the assimilation of the elements of nutrition by plants during dif- 

 ferent periods of their growth, H. Wilfarth et al., trans, by B. L. Emslie 

 {London [1907], pp. 72, pis. 2). — This is a translation from the (ierman of an 

 article already noted (E. S. R., 17, p. S.")*!). 



Report of the royal Bohemian agricultural academy at Tabor, 1906, T. 

 Erhex et al. (Ztxchr. LumUr. ]'cr):>iiclnr. Ostcrr.. 10 {1907). \<k ). pp. Jfll- 

 .'iS'n. — A brief review of the year's work at the school is given. Variety tests 

 are reported of 30 varieties of winter wheat, 10 of spring wheat, 10 of rye, 38 of 

 barley, 2i) of oats, 200 of potatoes, and 3 of fodder beets. 



The best yields of grain from among the winter wheat varieties were secured 

 from Cimbal, Kirsche, and Strube. The results with barley again showed the 

 sui)eriority of the well-selected common strains, as compared with sorts derived 

 from Chevalier and Imperial barleys. The highest grain yields were obtained 

 from Xolc Bohemia and Ilanna from Proskowetz. Svalilf Hannchen, Primus, and 

 Xolc Early ranked first in starch content. The lowest protein content was 

 shown by Hannchen and Xolc J. 1C> and J. 19. The best yield of oats were 

 secured from Svalcif Goldregen, Hwittling, and a number of newly bred varie- 

 ties such as Leutewitz Yellow, Strube Schlansted, and Kirsche Prolific. Of the 

 different potato varieties under test, Director Nydrie, Prof. Nilsson, and Brocken 

 led in starch production, with 4,950, 4,558, and 4,747 kg. of starch per hectare. 



The average yields of 3 varieties of fodder beets were as follows : Eckendorf 

 Ited 3(;9.3 kg., Eckendorf Yellow 354.8 kg., and Red Mammoth .338.1 kg. per 

 are. 



Tests of nitrate of soda and liquid manure as fertilizers for sugar beets were 

 made, the results indicating that the use of liquid manure, while not jn'oducing 

 as large yields as nitrate of soda, is more economical. The method of fertili- 

 zation had apparently no influence on the quality. 



In cooperative tests with 5 varieties of winter wheat, an average yield of 

 2,482 kg. per hectare was secured. The squarehead varieties survived the 

 winter well and ranked first in yield, while Landas Gigantea staod last. 



The yields in cooperative tests with oats were as follows: Duppau 3,107. 

 Strube Schlandsted 3,119, Svalijf Ligowo 3,013, and Heraletz Late 2,9.30 kg. per 

 hectare. 



Tli(,' leading potato varieties were classified according to their quality as 

 follow;-.: Nilsson, Maincrop, and Sophie as excellent; White King, Gryf, and 



