1618 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



Spitzenburg and other varieties haye 

 been very badly blighted; however, most 

 of the trouble on the apple is due to 

 blight in the blossoms or m the twigs, 

 but on the Pacific coast it is not at all 

 uncommon to see the Spitzenburg and 

 crabapples entirely killed. With the Rus- 

 sian apples, such as the Yellow Trans- 

 parent, Alexander, Red Astrachan, etc, 

 the disease has killed trees just as it 

 does pears. In the Middle West in the 

 states of Illinois, Iowa, Nebraska and 

 Kansas, the injury to the apples is found 

 to be very severe The rich prairie soils 

 of these states, together with an ample 

 supply of rainfall during almost the en- 

 tire growing season, produces a rank 

 growth which causes the trees to become 

 very subject to the disease. The disease 

 has moved steadily westward with the 

 settlement of the country, but for a long 

 time the wide stretch of plains free from 

 orchards and giving no opportunity for 

 the disease to lodge, resulted in complete 

 freedom from this pest on the Pacific 

 coast It IS only since about 1898 that 

 the disease became known in Colorado, 

 and about the same time we find its 

 occurrence in the neighborhood of Van- 

 couver, British Columbia. About 1901 

 the disease broke out in force in the San 

 Joaouin valley, California, but it was 

 probably two or three years developing 

 before attracting much attention. It has 

 finally resulted in the destruction of 

 practically all of the orchards In San 

 Joaquin valley, and has moved up into 

 nearly all the districts of the great Sac- 

 ramento valley, and in many of the 

 smaller adjacent valleys. I know of only 

 one valley, namely, the Santa Clara val- 

 ley, which so far seems to have escaped 

 infection. It is only through the efforts 

 of the commissioners and inspectors in 

 this valley that the valley has been kept 

 free from this dreadful disease To show 

 the extent of the injury to California I 

 may state that fully two-thirds of the 

 pear trees of the Bartlett variety have 

 been destroyed. As an instance showing 

 the extent of this calamity, I note H the 

 report for 1901 and 1902 issued by the 

 California State Board of Horticulture, 

 that Fresno county had 125,000 pear 



trees; Kings county, 43,700 pear trees, in 

 1903 and 1904 we find that Fresno county 

 had only 1,500 and Kings county had 

 none. The disease has moved slowly up 

 the Sacramento valley, and by slow 

 stages over the mountains into the Rogue 

 River valley m Southern Oregon, where 

 its distribution is general, but under 

 complete control. 



The blight infection now extends into 

 the Umpqua valley some distance beyond 

 Roseberg* Many have asked how the dis- 

 ease could have come from the upper 

 Sacramento river near Redding, which is 

 the northern limit of pear-growing in 

 California, into the Rogue River valley, 

 since there is a great mountain range 

 separating the two localities. However, 

 anyone riding over the Southern Pacific 

 railway and being observant would notice 

 that at every station along the railway, 

 and even at intermediate places, pear and 

 apple trees may be found; furthermore, 

 it may be noted that these pome fruits 

 have blighted more or less seriously, de- 

 pending, of course, upon the varieties as 

 well as upon the care given the trees or 

 the type of soil in which they are grow- 

 ing. These small plantings, together 

 with the native pome fruits, have been 

 stepping stones for the blight germ in 

 its passage from the upper California 

 orchards to the orchards of the Rogue 

 River valley 



The blight infection which we find in 

 British Columbia is an extension of the 

 Colorado infection which has passed 

 through the Salt Lake country in Utah, 

 and northwestward through the state of 

 Idaho and through Eastern Oregon and 

 Washington. Therefore, the Willamette 

 valley, together with the orchards north- 

 ward and west of the Cascades, have not 

 yet been invaded. In other words, the 

 two infections from the south and the 

 north have not yet met, but it is only a 

 question of time when they will come to- 

 gether. When blight does finally reach 

 these untouched districts the climatic 

 conditions will tend to favor infection 

 to a great degree. The increased rain- 

 fall as well as the late spring and sum- 

 mer precipitations favor infection, and 

 add difficulties in the way of control. The 



