DISEASES OF PLANTS. 411 



A summaiy of the experiments for the prevention of thepotiito scab 

 shows that the addition of lime in small quantities to the soil of the 

 experimental held increased the amount of scab; that the jiresence of 

 the organism in the soil tends to increase the infection of succeeding 

 crops of potatoes, beets, and turnips, and the treatment of the seed 

 with corrosive sublimate before planting in infested soil is of little 

 avail in preventing scab; and that fresh barnyard manure exhibits less 

 tendency to induce scab than composted manure. The author states 

 that too nnich stress must not be laid ui)on this last conclusion, since 

 it is based on a single experiment. 



Experiments were conducted on the value of transplanting onions 

 for smut prevention, and although the general results are horticultural 

 rather than mycological tlie author's summary shows that — 



"(1) This method insui-es ii clean crop eveu iipou smutty land. 



"(2) Transplanted onions are less lialile to the attacks of cutworiys than onions 

 sown in the lield. 



"•(3) The crop matures earlier by 3 or 4 weeks. 



"(4) The crop is larger by an average of 50 per cent or more with native varieties, 

 and the average increase with large foreign varieties may exceed 100 per cent. 



"(5) The individual bulbs are larger and mature more evenly. 



" (6) The increase in the size and quality of the crop, the earlier ripening, and the 

 lessened expense incident to the care of the plants after tran.splantiug, offset in a 

 measure the cost and labor of raising and transplanting the seedlings. 



•'(7) This method may bo applied with certain protit wherever it has been the 

 custom to grow onions from sets upon smiitty land, or in small quantities for home 

 use or small sales." 



A report is given of a leaf curl of Japanese plums. Fully 80 per 

 cent of the trees in the infected orchard were diseased, almost every 

 terminal shoot of the season's growth being aflected. Close pruning 

 and burning of diseased branches and spraying the trees with Bordeaux 

 mixture are recommended as possible means for eradication. The cause 

 of the disease is thought to be ExoaficuH mlrnhilh. 



A serious attack of tlie ])owdery mildew of grape ( Uncinula spiralis) 

 is reported, and thorough spraying of the vines is advised, the first 

 application to be given before Howering, the second immediately after 

 the fall of the flowers, and others at intervals as reiiuired. 



A melon disease is described, which is considered due to a si)ecies of 

 Alternaria that is probably the same as that described by E. F. Smith.' 

 The disease is "characterized by a wilting of the leaves, followed by 

 the a])pearance of small yellowish spots and blotches; these increased 

 rapidlj^ in size, the surface of the diseased areas became marked with 

 dark, concentric rings, the tissues became dry and brittle, and upon 

 all the older spots there was a copious growth of black mold distinctly 

 visible with a lens." Applications of Bordeaux inixture were appar- 

 ently without effect in checking the disease. 



A brief report is given of a severe attack of leaf spot of plums 



'Jour. Mycology, 7, p. 373 (E. S. R., 6, p. 557). 



