Popular Science Monthly 



100 



The entire coast-line was fringed by 

 a fence consisting of posts driven in the 

 ground at close inter\als, and llie spaces 

 between tliem were interwoven with 

 willow branches and brush. Soon the 

 strong winds blowing in from the ocean 

 banked a great wall against this fence 

 and eventually it was entirely covered 

 with sand. Then a second line of fence 

 was erected on the small lateral dune 

 thus created. In time this fence was 

 co\ered by the sand which banked up 

 against it. This operation was repeated 



The sand menace has disappeared, and 

 it cannot return. 



The situation on the Pacific ("oast is 

 similar in one respect to that which 

 confronted France. The sand is blown 

 inland by the high winds from the ocean. 

 The situation on the Atlantic Coast is 

 just the opposite, however. There the 

 sand is blown seaward, by winds coming 

 from the land. 



In the Columbia River region the 

 sand is much lighter in weight than the 

 sand of tiie Atlantic Coast, due to the 



Sand dunes about L _ 



many times and then other means of 

 increasing the size of the dune were 

 used. Native grasses that thrive in 

 sandy soil were planted along the top of 

 the dune; this served to keep its height 

 as uniform as possible by preventing 

 the winds from carving indentations in 

 the face of the pile. Pine trees were 

 planted along the top. These served to 

 check the wind-blown sand as the fences 

 had done in past years, and day by day 

 the dune grew in height and widensd 

 out. As it increased in size more pine 

 trees were planted. 



To-day a great forest 2,500,000 acres 

 in extent fringes the coasl-linc as the 

 result of this initial experiment. It 

 represents France's greatest supply house 

 of turpentine and lumber. The countr\- 

 King inland from it is rich antl fertile. 



large quantity of mica which it contains. 

 This makes it easily carried by the wind. 

 It also gives it great fertility when once 

 watered, so that with the reclamation of 

 the sand dunes there are possibilities of 

 cultivating profitable orchards and farm 

 lands in connection with the belts of 

 forest which will necessarily have to be 

 established. 



Many dunes in the lower Columbia 

 River valley are more thanthirt\- feet high, 

 and several even more. The accompany- 

 ing photographs illustrate some of the 

 prolilems caused b\' the dunes. Rail- 

 roads have spent thousands of dollars in 

 rough fences, known as hurdles, in an 

 effort to keep their tracks from being 

 submerged. Irrigation ditches have 

 been moved from time to time to prevent 

 th?m from being filled with sand. 



