bisEAsts oi" PLANTS; 445 



6nd the minimum inay fall below 5 per cent in gravel withoiit injury to the 

 tree except in decreasing its rate of growth. The optimum water content is 

 between 12 and 15 per cent. The behavior of lodgepole pine in dry situations 

 seems to warrant its use in afforestation experiments on the Great Plains. 



A well-developed forest cover either greatly reduces the amount of lodgepole 

 germination or causes the death of many of the young seedlings through com- 

 petition. The importance of working out a method of artificial control of the 

 forest cover is pointed out. Although lodgepole is inferior in the quality of its 

 wood to some of its competitors, its more rapid growth largely offsets this 

 disadvantage, and warrants its use in the afforestation of watersheds where 

 quick growth is required. 



In conclusion the future development and treatment of lodgepole forests are 

 discussed. 



The application of recent knowledge and skill in pine seed kilns, Wiebecke 

 (Ztschr. Forst. u. Jagdw., 42 (1910), No. 6, pp. 342-360) .—With the results 

 of his own investigations as well as those of Haack (E. S. R., 21, p. 441) and 

 others as a basis, the author discusses improved practical methods for drying 

 and storing pine seeds. Detailed plans are given for a seed kiln and stoi'age 

 house as worked out for a number of seed firms. 



The histology of resin canals in white fir, C. D. Mell (Amer. Forestry, 16 

 {1910), No. 6, pp. 351-356, figs. 9). — Descriptions are given of the structure of 

 the different groups of resin canals in white fir as worked out by Dippel and 

 reported in 1863. 



Stand conversion in Vienna woods, T. Micklitz {Centbl. Gesam. Forstw., 36 

 (1910), No. 6, pp. 243-257). — In this article the author points out that owing 

 to the diminishing financial returns from the pure beech stands in the north- 

 eastern part of the Vienna woods, these stands should be converted into beech- 

 oak or fir-spruce-beech stands, according to the locality. He discusses means for 

 bringing about these conversions, together with the work which has already 

 been done along this line. 



Sixth annual report of the state forester of Massachusetts, F. W. Kane 

 (Ann. Rpt. State Forester Mass., 6 (1909), pp. 109, pis. 11, fig. i).— This consists 

 of a statement of results obtained during 1909, including a record of exi^endi- 

 tures and recommendations concerning the future needs of the department. 

 Part 1 discusses general forestry and deals with the examination of woodlands 

 and practical assistance given owners, reforestation, forest nursery work, forest 

 fires for the year and protective measures used, forest education, literature, and 

 propaganda work. 



Part 2, giving a detailed account of the work of suppressing the gipsy and 

 brown-tail moths, is noted on page 4G.3 of this issue. 



The impregnation of growing timber, L. Ottinger (Jour. Soc. Chem. Indus., 

 29 (1910), No. 9, pp. 539, 540). — The author briefly describes the method in- 

 vented by L. S. Gardner for impregnating growing timber by the distribution 

 of artificial coloring matter through the fibers of the wood. 



Guayule (Parthenium argentatum), R. Escobar (Estac. Agr. Expt. Ciudad 

 Ju&rez, Chihuahua, Bol. 25, pp. 30, pi. 1). — ^An account of the guayule rubber 

 shrub relative to its history, botany, distribution, exploitation, extraction of 

 rubber, and reproduction. 



DISEASES OF PLANTS. 



Some fungus diseases of economic importance. Flora W. Patterson et al. 

 (U. a. Dept. Agr., Bur. Plant Indus. Bui. Ill, pp. 41, pis. 8, figs. 3).— In the 

 first part of this bulletin, discussions and technical descriptions are given of 

 the following diseases: A sedge disease (Kawakamia cyperi) prevalent at 



