13 



Aphides or plant-lice. — In some sections these are occasionally very 

 abundant, especially those of the apple and plum. Kerosene emulsion 

 is generally used to keep them down. 



Peach moth or peach twig-borer. — This insect was abundant in 1897 

 and again in 1900 and 1901. Winter spra^dngs with kerosene emul- 

 sion as determined by experiments on Snake River are very effective. 

 The sulphur-salt-lime wash seems to have no effect on the insect. 



BACTERIAL AND FUNGOUS DISEASES. 



Peach mildew {Sphaerotheca pannosa). — This disease is of general 

 occurrence in peach orchards, but does comparatively little damage. 

 Some years the disease is excessively abundant and other years scarce. 

 I have never been able to detect any other reproductive organs than 

 the conidia or summer spores. The fungus lives over winter on 

 young twigs. 



Up to the present time the disease has received no specific treat- 

 ment, and, in view of the relatively small damage done, it is probably 

 not proiital)le to spray against it. 



Pear blight. — This disease has been extremely destructive in almost 

 every part of the inland region for three years past. It is estimated 

 that 70 per cent of the pear trees in the region are either killed or so 

 badly injured as to be of little value. Some varieties have withstood 

 the disease much better than others, but strangely enough the same 

 variety seems to differ in its degree of resistance in different localities. 



CONDITIONS AFFECTING ORCHARDS IN THE INLAND UPLANDS. 



By the uplands are mear.fc the valleys and rolling hills having an ele- 

 vation of from 1,000 to 3,000 feet. In general, such lands comprise 

 the wheat-growing area of the inland region. Dependence is placed 

 entirely upon the rainfall, which in some localities is barely sufficient 

 to insure a crop. In wheat raising, indeed, the most common practice 

 is to summer fallow the land each alternate year, and in the drier 

 localities this is necessitated by the scanty rainfall. During recent 

 years a great acreage of fruit trees has been planted in such lands, and 

 the hardier fruits have proven veiy satisfactory investments. 



INSECT ENEMIES. 



Thus far there has been but very slight damage from insect pests. 

 How much this is due to the relative newness and isolation of the 

 orchards, and how much to the climatic conditions, it is difficult to 

 determine. The following notes on such insects and diseases as have 

 already appeared give the only indications we have as regards their 

 probable future behavior; 



