1903 FORESTRY AND IRRIGATION 307 



from the canals keeping the fields suffi- side and Redlands ; where ditches are 



ciently moist. lined, water is carefully measured, and 



Two acre-feet for an acre is an aver- citrus fruits are irrigated. This must 



age allowance for the arid region as a be furnished about two hundred days on 



whole. an average. It is equivalent to i|^ 



Five acres per miner's inch, or 250 acre-feet of water per acre irrigated, 



acres per second-foot, may be taken as This duty can be improved by the use 



the most economical use, say at River- of pipes. 



THE LOCUST. 



DESCRIPTION OF THE RANGE, HABITS, AND METHODS FOR 

 PLANTING ONE OF AMERICA'S MOST VALUABLE TIMBER TREES. 



BY 



WILLIAM L. HALL, 



CHIEF OF DIVISION OF FOREST EXTENSION, BUREAU OF FORESTRY. 



THE Locust (locally known as the Appalachian Mountains and the Mis- 

 Yellow or Black) (Robinia pscu- sissippi River, and extending west of the 

 dacacia} , originally indigenous to the Mississippi south of the 38th standard 

 mountainous region from Pennsylvania parallel as far as the Rocky Mountains, 

 to Georgia, and possibly as far west as It is also well adapted to the valleys of 

 Arkansas and eastern Indian Territory, Utah, Idaho, and eastern Oregon and 

 is now widely naturalized, through culti- Washington if planted on irrigated 

 vation and other agencies, throughout land. The planted groves to be seen 

 the United States east of the Rocky near Salt Lake City, Utah, and Walla 

 Mountains. Of recent years it is ap- Walla, Wash., are among the best in 

 pearing in great abundance on aban- the United States. 



doned hillside farms of Pennsylvania, The growth of the Locust is very 



Ohio, and Kentucky, and is also in- rapid, especially in rich soil, where dur- 



creasing in the southern portion of the ing its early growth it makes an average 



plains region west of the Mississippi. annual increase of 2 to 4 feet in height 



It rarely forms extensive pure growths and ^ to *4 inch in diameter. After 



except in southern Pennsylvania, Ohio, the first 25 or 30 years the average ac- 



and eastern Kentucky, where it is most cretion, both in height and diameter, 



abundant. Even in these localities it lessens, and by the fiftieth year usually 



is usually associated with other de- almost ceases. When the tree is once 



ciduotis trees, occurring in small scat- established, it sprouts vigorously from 



tered groves. the root, so that coppice growth is easily 



It has been more or less employed as maintained. The trees usually attain 



an ornamental tree and considerably a height of 40 to 80 feet, with a diameter 



planted in the Middle West for eco- of 2 to 3 feet. 



nomic purposes. Its tendency to sprout The largest and best Locust trees are 



from the root and its frequent failure generally found in well-drained, deep 



through the attack of borers have clayey, lowland soil, but it grows suc- 



brought it into disrepute in many sec- cessfully on sandy and gravelly soils, 



tions. However, these drawbacks are and is said to produce more durable 



not general and where present can, to timber there than in better situations, 



some extent, be obviated by proper On wet soils it is of slow growth and 



methods of management. short-lived. Its roots are shallow, and 



. The range for planting the Locust is where the soil is poor reach out to great 



extensive, covering the region between distances to obtain nutriment. The 



