1362 



ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



Bitter Root Yalley Fruit Growia^ 



R. W. Fisher 



The Bitter Root valley is situated be- 

 tween the Bitter Root mountains on the 

 west and the Hell Gate range of the 

 Rocky mountains on the east. The Bit- 

 ter Root mountains have an average 

 height of about 8,000 feet, and as a gen- 

 eral rule the snow is gone from the moun- 

 tains by July 15 or August first, except 

 on the north slopes far back in the can- 

 yons. In these canyons snow and small 

 glaciers provide the water for late irriga- 

 tions. The east-side mountains are not 

 nearly as high and have but little snow 

 to furnish irrigation water. 



The altitude of the valley varies from 

 3,198 feet at Lolo in the northern end of 

 the valley to 3,888 feet at Darby in the 

 southern end. The Como orchards west 

 of the town of Darby are several hundred 

 feet higher, or in the neighborhood of 

 4,000 feet above sea. 



The valley ranges in width from a few 

 hundred yards to 10 or 12 miles, none of 

 the tillable land being very far from the 

 mountains on either side. A large por- 

 tion of the tillable land is on the benches 

 sloping from the mountains, thus afford- 

 ing good air drainage. The larger por- 

 tion of the tree acreage is on these bench 

 lands where the slope is sufficient to give 

 both air and water drainage, while the 

 best grain land is on the bottom, where 

 air drainage is not so important. The 

 lands may be divided into three general 

 classes, in regard to situation: First, bot- 

 tom land, or lands near the level of the 

 river; second, upland bottoms, or lands 

 that are comparatively level, but several 



hundred feet higher than the river bot- 

 tom land; and third, the bench land that 

 is higher than the river bottom and has a 

 considerable slope. 



The river bottom land is poorest for 

 orchard purposes, both because of frosts 

 and water seepage. Some of the upland 

 bottoms are well adapted to growing 

 fruits. Such land is usually situated in 

 the mouth of a canyon, where the soil 

 is rich in plant food elements, and usu- 

 ally has a night wind from the canyon 

 which has considerable influence in pre- 

 venting frosts. As a genex'al rule the 

 bench lands are the best fitted for profit- 

 able fruit growing, because of better air 

 and water drainage. 



See article on Frost, 



Early fall and late spring frosts are 

 much more likely to occur on the river 

 bottom land. The frosts on the upland 

 bottoms depends much upon the location 

 of the land in regard to nearby canyons, 

 while the bench land as a general rule is 

 particularly free from injurious frosts at 

 any time. 



Except near the mouth of the numerous 

 canyons coming out of the Bitter Root 

 mountains, the general wind direction is 

 from the south or southwest. During the 

 winter months the cold winds come from 

 the north or northwest, but have little 

 influence upon the growth of trees or pro- 

 duction of fruit. 



Tables giving monthly mean maximum 

 and minimum temperatures, also dates 

 of last killing frosts in spring and first 

 of autumn, also monthly maximum and 

 minimum temperatures, all from Ham- 

 ilton, follow: 



Dates of last Killing Frosts of Spring and First of Autumn at Hamilton, Mont 



1903 



May 22 



Sept. 14 



1907 



May 25 



Sept. 18 



1911 



May 28 



Sept. 23 



1904 



May 25 



Oct. 5 



190S 



April 30 



Sept. 26 



1912 













1905 



May 18 



Oct. 9 



1909 



May 8 



Sept, 23 









1906 



May 6 



Sept. 15 



1910 



June 3 



Aug. 24 









