1918.] HORTICULTURE. 743 



During this period geographic differences in wheat prices, although still large, 

 have narrowed notably, especially as between importing Eastern and exporting 

 Western States, the diminishing price spreads being accompanied by decreasing 

 transportation costs and the development of distributive methods, and also 

 by a decline of wheat growing east of the Mississippi, as well as by a compara- 

 tive concentration of the national wheat production within the Western North 

 Central States. 



Although wheat production in the United States practically trebled during 

 the period of ISTl to 1915, in proportion to population it has remained sta- 

 tionary since 1882 to 188G, with 8.2 bu. per capita as against 8.3 bu. in 1911 

 to 1915. A notable and general decline was also observed in the proportion 

 of wheat to total improved land within the wheat belt, showing that increased 

 production was chiefly due to new areas brought under cultivation, together 

 with some slight increase in the yield per acre. Wheat production east of the 

 Mississippi dropped from 62.2 per cent of the total to 26.2 per cent, while 

 that of the Western North Central States (including Minnesota, Iowa, Missouri, 

 North and South Dakota, Nebrasl^a, and Kansas) increased from 26.1 per cent 

 to 51.8 per cent. It was only in the Mountain States (Montana, Wyoming, 

 Colorado, New Mexico, Arizona, Utah, Nevada, and Idaho), however, that any 

 considerable recent growth in the ratio of wheat production to population 

 was observed, due largely to new areas brought under cultivation, the per 

 capita production in this region increasing from 0.8 bu. during the period 1871 

 to 1875 to 20..S bu. in 1911 to 1915. 



Seed Reporter {U. S. Dept. Ayr., Seed Rptr., 1 (1918), 2Vo. 4, pp. 4).— 

 Tabulated statistics are presented on seed stocks of cowpeas, soy beans, le.spe- 

 deza, Sudan grass, sweet and grain sorghums, and millets based upon reports 

 made December 31, 1917, by shippers ; on forage plant seed permitted entry 

 into the United States during January, 1918 ; and on a comparison of retail 

 prices of vegetable seeds for 1918 with those for 1917 compiled from a large 

 number of retail mail-order catalogues received from representative seedsmen. 



Information relative to the clover-seed situatiT)n is presented, and jobbers* 

 prices for country-run seed, and quotations on recleaned seed, are briefly noted 

 for millet, forage and grain sorghums, Sudan grass, alfalfa, sweet clover, and 

 corn in the Missouri Valley. 



The .seed spring wheat situation in Minnesota, the Dakotas, and Montana is 

 reported as generally favorable, and the quality of the seed as excellent. 



Noxious weeds in New Zealand, A. H. Cockayne (Jour. Agr. [New Zeal.], 14 

 (1917), No. 5, pp. SS9-3J/4). — From 669 replies to inquiries sent out to farmers 

 by the New Zealand Department of Agriculture relative to the most serious 

 weeds of arable and pastoral land, a tabulated statement is presented showing 

 the 15 principal weeds reported for North Island and the same number for 

 South Island. Ten weed's of the latter group are weeds of arable land as com- 

 pared with only two of the former group, due to the difference in farm prac- 

 tice in the two localities. The State is divided into weed districts, giving the 

 three principal weeds for each. 



HORTICULTURE. 



Relation of the variability of yields of fruit trees to the accuracy of field 

 trials, L. D. Batchelok and H. S. Reed (U. S. Dept. Agr., Jour. Agr. Research, 

 12 (1918), No. 5, pp. 245-283, figs. 5). — In this paper the authors present the 

 results of a study at the California Citrus Substation of the nature and extent 

 of the casual variability of yields of fruit trees under field conditions and its 

 bearing on the reliability of plat trials. The results of previous studies relat- 



