8 FUNGI AND FUNGICIDES. 



it in this connection is imperative. The pear blight is caused 

 by a bacterium discovered by Prof. T. J. Burrill, of Illinois,, 

 and by him named Bacillus amylovorus. Its point of entry 

 into the tree is usually through the blossoms, although in some 

 cases it may find entry through wounds or abrasions in other 

 portions. The whole of the pomaceous family, including 

 apples, medlars, hawthorns, and quinces, is subject to attack, 

 but the pear especially so, and the tenderer varieties, as the 

 Bartlett, most of all. This disease has received marked atten- 

 tion from the Department of Agriculture at Washington, D. C., 

 on account of the serious inroads it has made in the pear sec- 

 tions of the East, and Prof. M. B. Waite has made an especial 

 study of it for many years past. In response to an invitation 

 from the Commission of Horticulture last fall, Professor Waite 

 was detailed to study the disease in California, and under his- 

 direction a series of experiments has been made. So far the 

 only method of fighting this disease, and the one which has 

 been in vogue for many years in the East, is to cut out the 

 affected portions of the tree well below the point of infection. 

 An important feature of this work is the disinfection of the 

 tools used in the cutting-out process. Unless this is properly 

 done, the tools themselves may become the medium of distribu- 

 tion of the disease. Professor Waite is positive in his assertion 

 that if the work of cutting out the infected portions is con- 

 scientiously and generally performed, there is little danger to- 

 be apprehended from this disease. 



GOOSEBERRY MILDEW. 



In some sections of the State it is almost impossible to raise 

 good gooseberries, on account of mildew. This fungus appears 

 in the spring upon the newly developed leaves and buds, and 

 later appears as a white powdery mass, caused by the numerous 

 ^fenuaoer spores. Later in the* season it attacks the young 

 berries, which are rendered unmarketable, or in very bad cases 

 the entire crop drops prematurely. 



Spray with a solution of potassium sulphide when the leaves 

 commence unfolding, and repeat in from two to three weeks. 



During the winter remove all old canes and spray with the 

 Bordeaux mixture (formula B). 



