DISEASES OF PLANTS. 53 



soda. Copper sulphate was used in the flowage on the floodmg sections at the 

 state bog on June 3 and 16 from 11 to 23 hours, but the effects on the crop as to 

 quantity and keeping quality can not yet be announced. Resanding seems to 

 favor the development of fungus disease. 



Cranberry spraying' experim^ents in Massachusetts in 1912, C. L. Sheae 

 (Ann. Rpt. Cape Cod Cranherry Growers' Assoc, 26 {1913), pp. 9-14). — The 

 author reports that Box'deaux mixture materially lessens cranberry diseases, 

 greatly reducing not only the rot or softening of berries which develops before 

 picking but also much of that which ordinarily develops in storage and trans- 

 portation, in addition to its stimulating influence on the vital activites of the 

 growing plant. It is claimed that four thorough sprayings should prove satis- 

 factory and profitable, the cost of application varying according to the condition 

 of the vines at the time. 



Citrus canker, F. A. Wolf and A. B. Massey {Alabama Col. 8ta. Circ. 27 

 {1914), PP- 97-102, figs. 6). — According to the authors, their attention was 

 called early in 1914 to a citrus disease in the vicinity of Mobile, Ala., to which 

 the popular name citrus canker was given. A study has shown that the disease 

 is widely distributed throughout southern Alabama and it is believed that it 

 exists in other Gulf States. 



Grapefruit seems to be more subject to the canker than any other citrus fruit, 

 the leaves, young twigs, older branches, and fruit all being subject to attack. 

 On Citrus trifoUata the disease is thus far known to attack only the twigs and 

 branches. The Satsuma orange seems to be slightly subject to the attack, a 

 .^spotting of the leaves being the only evidence so far observed. The sweet 

 orange is said to be more resistant than the Satsuma, and the kumquat is not 

 subject to attack. 



Several fungi have been found associated with the spots and cankers, but the 

 authors consider it caused by a species of Phoma. Inoculation experiments 

 made from pure cultures taken from grapefruit twigs developed the character- 

 istic symptoms of the disease in about three weeks. 



Experiments are being conducted for the control of the disease, and the pre- 

 liminary results indicate the effectiveness of spraying with Bordeaux mixture, 

 ammouiacal copper carbonate, or soluble sulphur. As a precaution the authors 

 recommend the removal and burning of all diseased parts and spraying the trees 

 thus pruned at intervals of several weeks. 



A gumming disease affecting lemon fruits, E. Jaevis {Queensland Agr. 

 Jour., n. ser., 1 {1914), No. 5, pp. 345-348, fig. 1). — ^A report with discussion is 

 given of a diseased condition appearing annually in late summer and autumn 

 on several varieties of lemons growing on different classes of soil and on trees 

 from grafts on different stocks. 



The disease is provisionally regarded as bacterial, other factors probably 

 being involved. Unsuitability of climate may be primarily responsible and 

 .suspicion as regards the carrying of infection attaches also to a bug {Biporiilus 

 biMx), which is vers^ active during the hot months when the disease becomes 

 most noticeable. 



A bacterial disease of Erodium and Pelargonium, I. M. Lewis {Phytopa- 

 thology, 4 {1914), No. 4, pp. 221-232, pi. 1). — This disease is said to have been 

 first desci'ibed by Heald and Wolf from the vicinity of San Antonio, Texas 

 (E. S. R., 2G, p. 645), and subsequent studies confirmed the statement that the 

 spot is caused by bacteria. The author's attention has been called to it not 

 only on Pelargonium, but also as producing a spot on the leaves of E. texanum. 



The spots are first reddish-brown in color, but soon change to black, and ulti- 

 mately the affected tissue becomes dry and the leaf withers and falls away. 

 The organism, to which the name Bacterium {Pseudomonas) erodli n. sp. has 



