196 BOTANICAL GAZETTE [FEBRUARY 
relatively unimportant. Lists of species present three and four years after the 
eruption are given.—GEo. D. FULLER. 
Soil moisture.—The increasing demand for the use of quantitative studies 
of soil moisture in ecological and agricultural studies makes ALWAy’s® investi- 
gation of methods for the accurate determination of the hygroscopic coefficient 
very timely. Hi~carp’s method is found to give reliable results, but certain 
changes in details of manipulation are found to be desirable as matters of con- 
venience. Two important conclusions are that the amount of hygroscopic 
moisture absorbed increases with rise of temperature, and that 12 hours’ 
exposure to saturated atmosphere is sufficient, provided the soil layer is very 
shallow.—Geo. D. FULLER. 
A new disease of wheat.—SmitH® has announced the appearance in the 
Middle West of a new disease of wheat, which he says “is a matter of much 
concern.” The disease has been known since 1902, but the destruction of 
winter wheat in 1917, which has generally been ascribed to winter-killing, 
led to the suspicion that a part of the loss might be due to this new disease. 
It is believed to be of bacterial origin, and promises to be difficult to 
control. 
The disease attacks not only the leaves, glumes, awns, rachis, and stalk, 
but sometimes also the kernel itself, suggesting that it is carried over from 
year to year on the seed.—J. M. C 
Vegetation of Colorado.—A valuable bulletin by Ropprns™ is a continua- 
tion of his work on the vegetation of Colorado in its relation to climate.” 
Comprehensive tables show what is known about the climates of the state as to 
temperature, precipitation, frost, humidity, length of growing seasons, etc. 
Following the statistical matter is a brief account of the chief types of vegetation 
and their relation to agriculture, under the following headings: grass-steppe, 
shrub-steppe, chaparral, pinyon pine-juniper woodland zone, yellow pine 
forest zone, lodgepole pine passe zone, white fir forest zone, Engelmann spruce 
forest zone. Maps and charts are freely employed. Useful lists of the more 
important trees, shrubs, and herbs are given. Publications such as this for 
other states would be of great value to botanists as well as to farmers.—. 
FRANCIS RAMALEY. 
Atway, F. J., and others. Some notes on the ep ipasagmaets of the hygro- 
scopic coefficient. Jour. Agric. Research 11:147-166. 
9 Sito, Erwin F., A new disease of wheat. se oe Research 10:51-53- 
pls. 4-8. 1917. 
ROBBINS, WILFRED W., Native vegetation and climate of Colorado in their 
relation to agriculture. Bull. no. 224 Colo. Agric. Exper. Sta., Ft. Collins, Colo. 1917. 
™ Bot. Gaz. 49:256-280. 1910. 
