DISEASES OF PLANTS. 847 



choice between them. The solution of Bordeaux mixture when one- 

 half the quantity of lime was used did not color the plants as much as 

 the standard mixture, and on this account might be preferred where 

 ornamental plants are sprayed or where there is dauger of staining 

 fruit. 



The effect of disinfectants upon the growth of seed potatoes was 

 tested, the seed being soaked 1.] hours in a 1:1,000 solution of corro- 

 sive sublimate. The seed tubers were soaked in this solution on the day 

 of planting, and 46 and 9G days before planting. Comparisons were 

 made with seed potatoes treated with formalin solution. The general 

 conclusions drawn are that disinfecting with corrosive sublimate just 

 before planting retards the early growth of plants, while if performed 

 I£ to 3 months before planting there is no such effect noticed. The use 

 of formalin seemed to exert no retarding effect, but is said to have 

 slightly stimulated the growth. 



Brief notes are given on the diseases of apples observed during 1896. 

 The most serious of these troubles is called the apple scald, and seemed 

 most widely spread on Greenings. These apples, which appeared per- 

 fectly sound at the time of harvest, became discolored at various 

 periods during the winter, a light brownish tinge appearing in fairly 

 well-defined spots, which became more or less diffused over the surface. 

 This light color passes to a dark-brown shade, and usually terminates in 

 a black rot. Associated with the black rot is usually a fungus, but 

 tjiis is a secondary affair, the primary discoloration being due to a 

 breaking down of the tissues of the fruit. Various theories are given 

 relative to the conditions which may cause these diseases, the con- 

 sensus of which is that the fruit had not attained perfect maturity at 

 the time of storing. The author discusses the relation of conditions in 

 the storeroom to the development of the scald, and shows that tem- 

 perature and ventilation are important factors in its development. 



The observations on oat smut were continued from the previous year, 

 and the percentage of smut on the different varieties and plats for 

 1895-'9G are tabulated. The effect of the Jensen hot-water treatment 

 on the yield of oats was tested, and where perfectly clean untreated 

 seed was used there was no gain, and there may have been a decrease 

 in the yield due to the hot- water treatment. 



The studies on onion mildew reported previously in the report of 

 this station for 1895, p. 113 (E. S. K., 8, p. 994), were continued and 

 the conclusions reaffirmed. Field experiments were made with fungi- 

 cides to test their efficiency in preventing the onion mildew, but the 

 solutions did not adhere well to the leaves, and the Bordeaux mixture 

 proved quite injurious on account of its too great strength. No mildew 

 appeared in this field on any of the plats, consequently the fungicidal 

 values were undetermined. 



The cause of a brown rot in cruciferous plants, E. F. Smith 

 (Centbl. Bate. u. Par., 2. Abt, 3 (1897), Ms. 11-12, pp. 284-291; 15-16, 

 pp. 408-415; 17-18, pp. 478-486, pi. 1). — The author has made a study 



