BUREAU or PLANT INDUSTRY. 26 1 



Prevalence or fruit diseases. — The season of 1910 closed with 

 only a moderate prevalence of diseases of the apple. The fruit spots 

 and leaf blights were about average, though apple scab was moder- 

 ately bad in the North and cedar rust exceptionally severe in the- 

 Appalachian Mountain region from Pennsylvania to Tennessee; yet 

 the total injury by fungi was below the average. This was due partly 

 to thorough spraying and partly to the dryness of the season. The 

 peach crop, though heavy, was exceptionally free from fungous 

 injuries. 



In the spring of 1911 frost injuries accounted for the widespread 

 destruction of peach blossoms from Pennsylvania southward. Much 

 injury to apple blossoms was caused by frost, not only in the East, 

 but in Colorado and in the Pacific Northwest. To the dry spring 

 is due the remarkable freedom from the fungous fruit spots and leaf 

 l)lights of the apple in the Eastern States, and this cause, together 

 with the general cutting down of the red cedars in some sections, has 

 greatly reduced the attacks of the cedar-rust fungus. 



On the other hand, the extreme heat caused tjie new combination 

 spray of lime-sulphur solution and arsenate of lead to produce a 

 considerable injury on the fruits. This injury, while conspicuous on 

 some specimens, covers only a small percentage of the crop and is 

 insignificant in comparison with the benefits. The widespread uso 

 of lime-sulphur solution on the apple and the combined self-boiled 

 iime-sulphur solution with arsenate of lead on the peach has re- 

 sulted in the Eastern States in the product! ju of a crop of very 

 much finer quality than usual of both these important fruits. Ex- 

 periments on the apple powdery mildew in California have been 

 continued, giving excellent results in its control. A large number of 

 fungicides have been tested both in California and in Virginia in the 

 effort to still further improve the mixtures for spraying fruit trees. 



Pear-blight eradication. — The work of pear-blight eradication 

 in California has been continued about the same as last year, and 

 excellent results have come through the widespread application of 

 department methods by the growers. Eeports from California indi- 

 cate that the pear crop for the season of 1911 will be one of the 

 largest and of the finest quality. The fine pear orchards of the 

 Rogue River Valley, where Mr. P. J. O'Gara carried out the depart- 

 ment methods, continue in their prosperous condition. Mr. O'Gara 

 resigned his position in the department, but continues his work in the 

 same locality, the people of the valley having employed him to de- 

 vote his entire time to pear-blight eradication and similar work. 



Little peach and peach yellows. — The diseases known as little 

 peach and peach yellows have been somewhat less severe in general 

 over the country, though they were very destructive in some locali- 

 ties. As peach yellows seems to be progressing southward, an elTort 

 was made to find the southern boundary of the disease. This line 

 has been partly mapped, particularly from the Atlantic seaboard 

 through the Allegheny Mountain region. 



Pecan scab. — Work on pecan scab, pecan rust, and other diseases 

 of this excellent nut has been continued in South Carolina. Georgia, 

 and Florida. Conclusive demonstration has been made that the 

 scab can be controlled on both leaves and fruit by spraying with 

 Bordeaux mixture; but the department ordinarily advises the plant- 



