1010] BOILS- FERTILIZERS. 32] 



Reference is also made to miscellaneous analyses of ashes of mixed timbers, 

 which showed from 0.0G to 5.04 per cent of potash. A table is Riven of 

 analyses of ashes of different kinds of Australian woods, in which the potash 

 varied from 0.13 per cent in gray ironbark to 9.28 per cent in mountain ash. 

 a potash content of 18.67 per cent is reports l Cor Knvi insignia and iO.71 per 

 cent for bracken fern. 



The effect of liming 1 on crop yields in cylinder experiments, .1. <:. LlPKAH 

 and a. \v. r.i.Air. {Soil SoL, 6 (1918), No. 2, pp. 157-161, flga. 3).— The authors 

 describe certain modifications in soil treatment in the cylinder experiments 

 which have boon In progress at the Now Jersey Experiment Stations since 

 1898 (B. S. K., 89, p. 817). The treatments under consideration comprised an- 

 nual applications representing 1G0 and 320 lbs. of sodium nitrate per aire and 

 of ammonium sulphate and dried blood in quantities equivalent to ."."J 1 * lbs. of 

 sodium nitrate per acre. All cylinders also received annual applications of 

 acid phosphate and potash at the rate of G40 and 320 lbs. per acre, respectively, 

 and in addition generous amounts of ground limestone were applied at the 

 beginning of the experiment. All treatments were made in triplicate, and be- 

 ginning with the spring of 100S the A cylinders in each series received no further 

 additions of lime, the B and C cylinders received generous applications of ground 

 limestone once in each 5-year rotation, and in the C cylinders a legumi- 

 nous green manure crop (vetch and crimson clover) was grown twice in each 

 rotation. Tabulated data are presented showing the yield in dry matter for 

 each cylinder for each year of the 20-year period, 189S-1017, inclusive, and a 

 comparison is made of the yields obtained in the first and second 10-year periods. 



The average yields for all treatments for the first 10 years amounted to 

 222.4, 223.1, and 215.2 gm. for the A, B. and C cylinders, respectively ; and for 

 the second 10 years 128. 9, 205.1, and 24;".;" gm. per cylinder, respectively. The 

 differences observed between the various treatments are briefly discussed, and 

 the conclusion is reached that " the continued use of acid phosphate, muriate 

 of potash, nitrate of soda, sulphate of ammonia, and dried blood, in amounts 

 corresponding to those employed in the experiments described here, is bound 

 to lead, sooner or later, to an unsatisfactory soil reaction and to the need of 

 generous applications of lime. Indeed, the writers are convinced that suffi- 

 cient stress is not laid on the importance of systematic and adequate liming 

 of land whose production is to be brought up to constantly higher levels by 

 the generous use of commercial fertilizers. Emphasis is also laid on the im- 

 portance of introducing leguminous crops in the rotation at frequent inter- 

 vals for the purpose of increasing the supply of available nitrogen and also to 

 maintain a good supply of organic matter." 



Experiments with lime and marl, IT. R. Citristenskn (Tidsskr. Planteavl., 

 25 (191S). No. 3. pp. 377-522, fig. 1) .— The results of experiments with lime 

 and marl carried on for a series of years at several Danish experiment stations 

 are reported at length and data from the different experiments are tabulated in 

 detail. The object of the work was to compare marl and lime, the use of 

 different quantities of the two substances, and the use of different forms of 

 lime. The soils upon which the tests were made included acid and neutral 

 clay soils and light neutral and light, strongly acid, sandy soils. Laboratory 

 tests showed that samples of these soils, with only one exception, wore in- 

 capable of developing Azotobacter. 



The available plant food content of the soil proved to be one of the greatesl 

 factors in determining the effect of lime on lime-poor soils, the effect of the 

 applications of lime or marl on such soils increasing as the fertility of the soil 

 decreased. In this connection it is pointed out that, where experiments with 

 oats and crop mixtures were co(fciucted for a series of years and the fertility of 



