I902. 



FORESTRY AND IRRIGATION. 



37 



11. The Saint Mary Diversion Canal. 



Another reclamation project recom- 

 mended b}' the Secretary of the Interior 

 is that of the St. Mary Canal, taking 

 water from the northern part of the 

 Rock}- Mountain region and conducting 

 it across gravel ridges to the drainage 

 flowing eastward. These gravel ridges 

 force the water to flow north, and it is 

 proposed to restore the ancient pre-gla- 

 cial drainage by cutting across the inter- 

 posing barriers. 



On the extreme right of the picture is 

 shown a dam holding back flood waters 

 in St. Mary Lake. From this a canal 

 leads along the side of the gravel-cov- 

 ered hills, and on the left passes through 

 a gap occupied by a small lake, finally 

 crossing the headwaters of Milk River. 



It will be necessary to carry the water 

 acro.ss the North Fork of Milk River to 



the South Fork, into which it can be 

 turned, or conducting it a few miles 

 farther, allow it to flow into streams 

 tributary to the Marias. 



The water can either be allowed to 

 flow in the natural drainage and be 

 taken out by ditches at various points, 

 or it can be kept in the canal and dis- 

 tributed to the great l)ody of public 

 land in northern Montana between the 

 Milk and Missouri Rivers. 



There are several alternative projects 

 to be considered, but it has been esti- 

 mated that for one of these the co.st 

 of taking out a canal to carry i , 200 

 cubic feet per .second of the stored flood 

 waters will be, in round numbers, 

 $1,000,000. This will bring the water 

 to the head of Milk River or to vacant 

 land in the \-icinit\'. From here the 

 distribution .sy.stems can be built l)y the 

 settlers. 



FOREST CONDITIONS OF THE HAWAIIAN ISLANDS. 



By W. R. Castle. 



HAWAII is dissimilar from some 

 tropical countries, in that it does 

 not contain a solid mass of tropical vege- 

 tation extending from the mountain 

 summits to the ocean. On the contrary, 

 it needs forests, and there is presented 

 here a noble opportunit}' for verj' fine 

 work in this line. 



In general, it may be said that the 

 axis of Hawaii lies directh- across the 

 path of the prevailing winds and ocean 

 currents. The mountain chains form 

 the line of this axis, excepting on the 

 islands of Hawaii and Maui, where the 

 mountain system is represented by three 

 huge mountain masses in the former, and 

 two in the case of the latter island. We 

 therefore find that the forests exist in 

 lines coincident with the ma.sses of vapor 

 swept in by the winds ; that is, as a 

 rule, all of the northeast sides of all of 

 the islands are covered with forests, and 

 in some cases very densely. The forest 

 growth has, in man}' cases, flowed over 

 the tops of the mountains down to the 

 southwest or leeward sides. In some 

 in.stances a break in the mountain line 



has occurred and the moisture passing 

 through has resulted in a covering of 

 forests along the lines of the valley or 

 valleys, running toward the southwest. 

 The southwest shores of nearly all of 

 the islands are arid and barren, although 

 the soil is extremely fertile. Wherever 

 water has been brought to these slopes 

 and plains the great fertility is shown in 

 the production of abundant crops. 



Some attempt has been made in past 

 years to clothe a few barren hillsides of 

 the country with forests. Many years 

 ago the ' ' algeroba " ( a tree of the acacia 

 family, probably bearing .some resem- 

 blance to the mesquite tree of the south- 

 western United States) was introduced, 

 and it has proven a very great advantage 

 to this country, growing luxuriantly on 

 the barren plains near the sea; making 

 splendid firewood, shading the plains, 

 producing a bean which isof great benefit 

 and value to live stock, and enriching the 

 ground b}- the very copious deposits of 

 leaf mold. These trees ha\-e been placed 

 upon the leeward sides of most of the 

 islands and are doing well. Their growth 



