19181 



AGRICULTURAL BOTANY. 

 Analyses of flue dusts. 



425 



It is estimated that there are 300 furnaces in full blast in Great Britain and 

 that each produces 20 tons of black, 5 tons of red, and 1 ton of cream-colored 

 flue dust per week. On the basis that the black dust contains 2.5, the red 7, 

 and the cream-colored 10 per cent of potash, their total annual production would 

 be about 15,000 tons of potash, of which at least 50 per cent is considered 

 to be available. 



Commercial fertilizers, P. L. Hibij.vkd (California Sta. Bui. 286 (1917), pp. 

 117-166). — This reports the results of fertilizer inspection work for the year 

 ended June 30, 1917. A total of 506 samples of fertilizers and fertilizer ma- 

 terials was received, 460 being official samples. Deficiencies greater than those 

 allowed by law occurred in 126 samples. 



Fertilizer analyses, H. B. McDonnell et al. (Md. Agr. Col. Qttart., No. 77 

 (1917), pp. 31). — This is a report of the fertilizer inspection and analysis in 

 Maryland for the period from February, 1917, to June, 1917, inclusive. 



Commercial fertilizers, J. L. Hills, O. H. Jones, and G. P. Anderson (Ver- 

 mont 8ta. Bui. 206 (1917), pp. 5-52, pis. Jf). — Analyses of 171 licensed brands of 

 fertilizers, representing the output of 18 companies and sold in Vermont during 

 1917, are reported. The quality of the crude stock used is reported as being be- 

 yond reproach. All but 4 of the 171 brands carried appreciable amounts of 

 mineral as well as of organic forms of nitrogen, and about J contained potash. 

 Guaranties were met in 81 per cent of the brands tested. The average selling 

 price was $32.65, but no trade valuation was made owing to the unsettled con- 

 ditions of the fertilizer industry. 



AGRICULTURAL BOTAITY. 



Plant associatious of western Pennsylvania with special reference to physi- 

 ographic relationship, II, J. E. Cribbs (Plant World, 20 (1917), No. 5, pp. 1^2- 

 157, fujs. S). — The author states that plant associations of western Pennsyl- 

 vania bear a close relation to the topographical features of that region, so 

 that a given type of vegetation may be expected to grow in widely separated 

 similar environments. This is due to its close relationship to certain factors 

 which are practically decisive. 



Desiccation produces much the same result whether due to wind or to sun- 

 shine. Soil composition produces no striking differences. Relative humidity 

 resolves itself into a question of soil moisture, which is the most important of 

 the factors determining, directly or indirectly, the composition of the associations. 

 High soil humidity inhibits oxidation, so that acids and other plant by-products 

 accumulate in sufficient quantity to exert possibly a direct influence upon the 

 vegetation. Decay processes may draw oxygen from the supply in the water 

 sufficiently to affect growth. Retention of detrimental materials in the soil is 



