CRESTED WHEATGRASS 3 



grass and slender wheatgrass have frequently yielded more than 

 crested wheatgrass the first 2 or 3 years, after which the slender wheat- 

 grass tends to die out and the bromegrass becomes sod-bound, whereas 

 the crested wheatgrass continues to produce satisfactorily even under 

 limited moisture conditions. At the Northern Great Plains Field 

 Station, Mandan, N. Dak., a seeding made in rows in 1915 returned 

 its sixth highest hay yield in 1935, the twentieth year of production. 

 This planting has produced 25 consecutive crops. The highest 

 yield was 3,550 pounds per acre, in 1916, and the lowest was 146 

 pounds per acre, produced during the severe drought of 1936. The 

 average 3 T ield for the 25 years has been 1,675 pounds per acre. 



Crested wheatgrass is able to grow at low temperatures and as a 

 result makes earlier and more rapid growth than most other grasses 



MAJOR ADAPTATION 

 E3 MINOR ADAPTATION 



Figure 1. — Adaptation of crested wheatgrass. 



with which it has been compared. The grass is extremely drought 

 resistant and has survived the most severe periods of dry weather. 

 This characteristic is probably due to its extensive root system, 

 which permits storage of abundant food reserves and ready utilization 

 of water. Excavations have shown that the roots may penetrate to a 

 depth of 8 to 10 feet. During hot, dry periods the grass has the 

 ability to become more or less dormant and protects itself from injury 

 by this characteristic. With a favorable moisture supply, growth is 

 resumed upon arrival of the cool days of autumn and continues until 

 late in the season. Its ability to grow at low temperatures combined 

 with its efficient utilization of soil moisture enables the grass to crowd 

 out weeds where the moisture supply is limited. It is entirely re- 

 sistant to all extremes of cold. No reports of killing of an established 

 stand from either cold or drought have been made in areas where the 

 grass is adapted. 



Adaptation 



Crested wheatgrass is especially well adapted to the northern Great 

 Plains, where the temperatures are severe and the moisture supply is 

 limited, and westward to the Sierra Nevada Mountains (fig. 1). 

 In this general region it has proved particularly valuable for regrassing 

 abandoned croplands. Farther south it has not given as good results 

 except at altitudes of 5,000 feet or more. In the area adjacent to 

 the Plains on the east, other grasses are generally more satisfactory. 



