DISEASES OF PLANTS. 367 



treatments is of any practicable use. Indirect methods must be adopted for the 

 control of this disease, among them rotation of crops and trenching about diseased 

 areas to prevent the further spread. After cutting the cane the stumps should be 

 collected and burned, together with all the trash remaining on the field. In connec- 

 tion with the crop rotation, attention is called to the fact that sweet potatoes are 

 probably affected by the same fungus as that occurring upon the cane. 



A foot rot of wheat, A. B. Cordley {Oregon Sua. Rpl. 1902, pp. 66, tf7).— A dis- 

 ease of wheat is described as occurring in a number of regions in Oregon in which 

 every stalk is infested at the base by a fungus, and the plants are seriously injured. 

 The disease is characterized by a blackening of the tissues in the lower part of the 

 stem, and microscopic examination showed the presence of a fungus mycelium which 

 as yet has not been determined. Whether the disease is a new one or not and 

 whether it is liable to become of economic importance are sul)jects for further 

 investigation. 



Inquiry concerning' amount of loss from smut of wheat and. oats in Illi- 

 nois, A. D. Shamkl {Illiiiuis Stu. CVrc.s. 54, 55, pp. 3 each, fig. 1 encli). — Brief descrip- 

 tions are given of the smuts of wheat and oats. In order to secure data relative to the 

 prevalence of these diseases and the loss occasioned by them, reports of the percent- 

 ages of smut are requested in the circulars. 



The gummosis of fruit trees, P. Passy {Rev. Hort \_Paris], 74 {1902), No. 11, 

 pp. 269, 270). — A description is given of gummosis, the real cause of which the 

 author says is probably not known. It manifests itself by the accumulation in cavi- 

 ties under the bark of a substance analogous to gum arable and which results in the 

 ])reaking down of the cells of the plant, particularly of the medullary rays. Humid- 

 ity of soil, sudden variations in temperature, the destruction of the foliage, or other 

 factors which bring about marked physiological changes in the plant seem to favor 

 the production of the gummosis. In addition to these physiological causes, the 

 author states that certain fungi, among them Coryneum beyerlnckii, are able to pro- 

 duce similar conditions in certain of the stone fruits. Marked differences are noted 

 of the susceptibility of different varieties of stone fruits, peaches being exceptionally 

 susceptible, while apricots and cherries continue to live for a long time after being 

 attacked. As preventive measures the author recommends the aeration and proper 

 draining of the soil and subsoil in order to secure a better development of the trees 

 and, where the disease is due to attacks of fungi, spraying with Bordeaux mixture. 



Field work with bitter rot during- 1901, J. C. Blair and A. V. Steubenrauch ' 

 {lUhiois Sta. C'irc. 4o, pp. 27, figs. 2). — An account is given of field work undertaken 

 in cooperation with the Division of Vegetable Physiology and Pathology of this Depart- 

 ment. The efficiency of Bordeaux mixture was tested and information sought 

 regarding the value of winter treatments, of early spraying, and the relative value 

 of other fungicides in controlling this disease. The work was conducted by a number 

 of individuals under the immediate direction of the horticulturist, and the results 

 indicate that Bordeaux mixture when properly made and applied will jirotect apples 

 to a reasonable extent from bitter rot. The winter treatment of dormant trees seems 

 to be of no practical assistance in checking the disease, and early sprayings are no 

 more advantageous than reasonably late sprayings. In the comparative tests of 

 fungicides, Bordeaux mixture was found superior to the ammoniacal copper carbonate 

 solution. 



Prevention of bitter rot, T. J. Burrill and J. C. Blair {Illinois Sta. Circ. 58, pp. 

 3) — The object of this circular is to call attention to a recent discovery which seems 

 to give an opportunity for combating the bitter rot of apples. In general it may 

 be said that the distribution of the disease in the tree shows a conical shaped area 

 with the apex upward. The primary infection occurs at the apex of this cone 

 and this infection is said to start from a canker upon the limbs of the tree. These 

 cankers are described, and as preventive measures it is recommended that the trees 



