46 EXPEKIMENT STATION EECOED. [Vol.37 



and the spring of 1911 and offered with the view of calling attention to a 

 promising field of research. 



A practical method of preventing the damping-off of coniferous seedlings. 

 C. A. Scott (Jour. Forestry, 15 (1911), No. 2. pp. 192-196. pis. 2).— The author 

 here describes a practical method of sterilizing forest nursery seed beds with 

 high pressure steam to reduc-e the loss of evergreen seedlings by damping-off. 

 This method was recently developed with successful results at the Kansas 

 Experiment Station. 



The windbreak as a farm asset, C. G. Bates (U. S. Dept. Agr., Farmers' 

 Bui. 788 (1911), pp. 15, figs. 8). — This publication discusses windbreaks with 

 special reference to their use in protecting the fields and farm buildings from 

 the force of the wind, including planting instructions and kinds of trees recom- 

 mended for planting in different sections. Estimates are also given of financial 

 returns per acre to be expected from various kinds of windbreaks. 



To determine the total effect, whether beneficial or injurious, of windbreaks 

 on crop yields a number of crop measurements were made in Nebraska, Kansas, 

 Iowa, and Minnesota. The measurements as a whole indicate that with ordi- 

 nary field crops the farmer may count on a benefit from windbreak protection 

 wliich will make the loss of the area occupied by the trees negligible. 



Timber estimating in the southern Appalachians, R. C. Hall (Jour. For- 

 estry, 15 (1917), No. S, pp. S10-S21). — In this paper the author discusses meth- 

 ods employed in estimating timber and approving forest lands for purchase 

 under the so-called Weeks Law, together with new adaptations which have 

 proved especially valuable. 



Some problems in Appalachian timber appraisal, W. W. Ashe (Jour. For- 

 estry. 15 (1917), No. S, pp. S22-SSJi). — A paper somewhat similar to the above 

 discussing problems In timber appraisal work peculiar to the Appalachian 

 forests. 



The role of the microscope In the identification and classification of the 

 " timbers of commerce," 1. W. Baiijcy (Jour. Forestry, 15 (1917), No. 2, pp. 

 176-191, pis. S, figs. 2). — In this paper the author concludes that anatomical 

 keys for distinguishing woods as constructed by botanists and mlcro-scopists 

 have failed to receive the recognition and extended u.se that bave commonly 

 been predicted for them. Two important reasons fiv this failure, as here dis- 

 cussed, are limitations to the use of anatomical keys In the lumber business and 

 variability of anatomical characters. A careful study of some of the supposedly 

 most reliable diagnostic criteria, such as the distribution of wood parenchyma, 

 form and structure of the rays, type of pitting, etc.. Indicates very clearly that 

 these characters may fluctuate considerably, not only In certain families, 

 genera, and species, but also In different parts of a single tree. 



DISEASES OF PLANTS. 



[Report of the division of botany. — Bacteriology and pathology] CWash- 

 ington Sta. Bui. 1S6 (1917), pp. 19-25, figs. 5).— A pnipress reiwrt is given of 

 some of the more iniportant investigations being carried on by the division of 

 botany. Among those are studies of tomato blight, previous notes of which have 

 been given (E. S. R., 36, p. 350) ; Identification of fungus diseases; investiga- 

 tions of fire blight, an account of which has already been noted (E. S. R., 35, 

 p. 848) ; and wheat smut, also previously noted (E. S. R., 34. p. 644). 



In connection with the wheat smut investigations, two sources of Infection 

 have been discovered, the first from spores adhering to the wheat grain and 

 Infecting at the time of sprouting, the second from the spores which settle upon 

 summer faUow ground during the thrashing season. In the prevention of this 



