DISEASES OF PLANTS. 747 



outbreaks of potato blijilil in Ireland np to July 17, 1'.>()1). jnid the action taken 

 by the department to seeun^ a more general use of spraying' is briefly stated. 

 Tills includes the distribution of a larw number of leaflets dealing with the 

 prevention of potato bliijht by means of sprayinj,'. and grants and loans for the 

 purchase of spraying apparatus. In the counties covered by the report over 

 1.000 spraying machines have been distributed to date. A number of overseers 

 and assistants are employed whose duties require them to repair spraying ma- 

 chines, to sell machines at cost price, within certain limits, and to give demon- 

 strations in spraying. 



The potato rot (Phytophthora infestans), G. (Jand,\r.v (liol. Hoc. Af/r. Mcxi- 

 cana.' 33 (1909), Nos. 20, pp. 39.',-396; 21, pp. 412-^16; 22, pp. //,^5-'/28 ) .— A 

 description is given of the i)otato rot due to P. infestans, with suggestions for 

 its control, thorough si)raying with Bordeaux mixture being reconunended. 



The use of lime in agriculture, with special reference to its application to 

 finger-and-toe disease in turnips, W. E. Collinge (Jour. Cooper Research Laly., 

 1909, No. 1, pp. 15-27, figs. 2). — After discussing the manurial, chemical, and 

 physical effect of lime when applied to the soil, the author takes up its use in 

 connection with certain plant diseases, particularly the club root of cruciferous 

 jilants and potato scab. 



The application of lime to soils seems to favor the development of potato scab, 

 while if applied at the proper time and in considerable amount it seems to reduce 

 the tendency to the club root disease. Common lime at the rate of 2i tons 

 per acre, slaked to a fine powder, and thoroughly mixed with the soil, is usually 

 productive of the best results. The application should be made as soon as 

 liossible after the removal of a diseased crop and the surface soil should be 

 thoroughly mixed with the lime. Experiments show that the lime may be 

 more effectual on the second than on the first crop which follows its applica- 

 llon, and it is thought probable that the greatest effect from its application 

 will not be noted for several years. 



Notes on a nematode in wheat, E. C. Johnson (Science, n. ser., SO (1909), 

 No. 773, p. 576). — The author reports the appearance in different portions of 

 the United States in 1909 of a nematode in wheat. It was first discovered in 

 grain from California, and its presence has since been reported from Georgia, 

 West A'^irginia, and New York. 



The affected heads of wheat are similar in appearance to those attacked by 

 bunt. The glumes of the spikelets spread somewhat, and the places where the 

 kernels should be are occupied by dark galls full of nematode larvne. The 

 species is believed to be Tylenehus tritiei. which has long been known in 

 Europe, but apparently has not been previously reported in America. 



The author cites a letter from Dr. E. A. Bessey, who has been for several 

 years making a study of these parasites, in which it is stated that related 

 forms occur on species of Agropyron, Elymus, Calamagrostis, Trisetum, Chse- 

 tochloa, Agrostis, and Sporobolus in various parts of the United States, but that 

 he had not observed any form attacking wheat. The parasite is said to have 

 gained considerable headway in West Virginia and may prove a serious jiest. 



It is suggested that infested wheat should be cleaned tlioroughly before 

 sowing. It is thought probable that the hot-water treatment used for smut or 

 soaking the seed in a dilute solution of sulphuric acid would destroy the 

 nematodes, but further experiments are necessary before these treatments can 

 be recommended. 



The characteristics of apple-tree anthracnose, A. B. Cordley (Better Fruit, 

 .'i (1909), No. .',, pp. 13-17, figs. 6).— A description is given of the apple-tree 

 anthracnose, previously reported in a publication of the Oregon Station (E. S. R., 



