722 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



plough is shown to have fallen in Great Britain from 59 per cent, in the 

 period 1867-71 to 49 per cent, in the period 1897-1901. 



The returns of the estimated yield of crops in 1901 show that, although 

 Wheat was stated to be nearly a bushel per acre over average, the results 

 of the corn harvest generally were unsatisfactory. A deficiency in the 

 Turnip crop was only partially redeemed by a good yield of Mangolds, 

 while the Hay crop, both from clover and meadows, was unusually short. 

 There was, however, a heavy crop of Potatos, and a large yield of Hops. 



B. N. 



Alaska, Suggestions to Pioneer Farmers in. By C. C. 



Georgeson (U.S.A. Dep. Agr. Alaska Exp. Stn., Bull. 1; 7 plates; 

 1902).— A helpful body of instructions to intending settlers in Alaska, 

 describing all the various processes to be gone through before the farm is 

 in a condition to produce crops. Clearing the land, draining, building 

 silos, and fertilising are all described with a view to the scarcity of avail- 

 able appliances and the cost of introducing them. 



Freshly cleared land in Alaska is not capable of producing a paying 

 crop without a good deal of preliminary fertilisation, and there is a red 

 subsoil, said to be of volcanic origin, which is almost wholly sterile in 

 itself.— M. L. H. 



Alkali on Citrus-trees, Effect of. ByR.H.Loughridge (U.S.A. Exp. 

 Stn. California, Report for 1897-8, p. 99 ; plates and tabs.). — The effect 

 produced by the presence of alkali in the soil is both direct and indirect : 

 direct in its action upon the trees through their roots, and indirect in its 

 action upon the physical nature of the soil, and hence through the soil 

 upon the tree. The direct action, of course, varies with the nature and 

 amount of the alkali in the soil. Carbonate of soda is regarded as the most 

 dangerous of the alkali salts, because of its intense alkalinity and corro- 

 sive action on the rootlets. The chief injurious effect of chloride of 

 sodium upon plant-life is that of an antiseptic whose action seems to be 

 in the arrested development or killing of the nitrifying organisms in the 

 soil. Sulphate of soda is injurious when in large amounts, and its action 

 would seem to be chiefly that of preventing osmosis of the soil solution 

 inward into the cells of the roots. This must ultimately produce death. 

 In many affected orchards relief can be had by bringing the soil back to 

 its orginal tilth by proper tillage, by deep ploughing of the soil to break 

 up the compact hardpan condition caused by the alkali. As an aid to the 

 loosening of the soil a green -manure crop should be grown and turned 

 under to decay and give needed humus, which is an active agent in 

 maintaining good tilth. Alkali that has accumulated to a large extent 

 in the soils must be removed by thorough leaching of the soil around the 

 trees to depths of five or six feet ; the leaching, of course, being done by 

 water free from alkali. Reproductions of photographs are given showing 

 the difference in Orange trees grown in soils containing much and little 

 alkali, and valuable tables of the results of various analyses of soils 

 showing the percentages of alkali at various depths. — V. J. M. 



Alg^e, Destruction of. By L. Graebener {Die Gait. p. 520; 

 2/8/1902). — The author mentions how he destroyed the Algas in a tank 



