GRASSES FOR CANAL BANKS IN WESTERN SOUTH 



DAKOTA. 1 



By Abthub C. Dillmax. 2 Assistant Physiologist, Office of Alkali and Drought 



Resistant Plant Investigations. 



INTRODUCTION. 



In the construction of canals and ditches for the purpose of irri- 

 gation, the area of soil exposed and left bare of vegetation is very 

 large in the aggregate. Experiments have been conducted on the 

 canal banks of the Belief ourche Irrigation Project in western South 

 Dakota to determine what grass or combination of grasses will estab- 

 lish a satisfactory sod on such banks. This circular describes the 

 experimental work and gives such recommendations for seeding 

 canal banks on this project as are justified by the results thus far 

 obtained. 



THE NEED OF A GRASS COVERING. 



The advantages of a grass sod on the canal and ditch banks are, 

 chiefly, to prevent erosion of the soil, to prevent the growth and 

 spread of weeds, and to furnish pasture for live stock. 



The erosion of the loose soil on the steep slopes of the ditch 

 banks is often serious. Most of the soils of this region are composed 

 of fine particles and therefore wash more readily than soils of a 

 coarser character. The amount of erosion on any short section of 

 ditch bank might not be considered serious, but the quantity of 

 soil washed down into the canals and ditches from over 300 

 miles of canal banks must be enormous. 3 Any covering of sod 

 which will prevent or lessen this erosion will mean a real economy 

 in the maintenance of the project. 



One of the chief uses of a grass covering is to exclude the growth 

 of annual weeds which usually infest ditch banks. Unless a perma- 



1 Issued Mar. 1, 1910. 



2 The investigations here reported have heen conducted hy the writer, representing the 

 Office of Alkali and Drought Resistant Plant Investigations, in cooperation with Trof. C. V. 

 Piper, of the Office of Forage-Crop Investigations, who has furnished useful suggestions, 

 as well as most of the seed required. 



8 Mr. F. C. Magruder, project engineer, writes that there arc T,0 miles of main canal. 

 85 miles of main laterals, and 014 miles of small laterals on the Bellefourche Project. 

 These canal banks have a total area of about 1,200 acres. 



[Cir. 115] 23 



