202 CROPS FOR ALKALI LAND 



are generally more sensitive than the wild ones. Observa- 

 tions of the more important meadow and pasture grasses 

 have been made, but the number of different conditions or 

 combinations of salts under which. they have been studied 

 makes the limits indicated for them of less value than for 

 plants which have had a larger number of studies made 

 of them. 



Timothy (Phleum pratens) is reported by Kearney (17) 

 to succeed in the presence of 4000 to 6000 parts per mil- 

 lion of white alkali and perhaps more where the dis- 

 tribution of alkali is uniform. Traphagen (29) places the 

 limit below 10,000 parts per million where the salts are 

 mostly of the sulphate type. Near Baker City, Oregon (3) , 

 an average crop was produced on land containing 700 parts 

 per million of sodium carbonate. Timothy, like almost 

 all of the grasses, has very small seed, and it is very im- 

 portant in getting a stand with such seed that the seedbed 

 be free from alkali. Unless the alkali can be washed out 

 of the seedbed until the grasses get a good start, it is al- 

 most useless to seed these crops on alkali land. Timothy 

 can be kept moist throughout the year, and because keep- 

 ing the soil moist dilutes the alkali the growth is much 

 more satisfactory than where less water is used. 



Orchard grass (Dactylis glomeratd) is probably a little 

 more resistant to white alkali than timothy. Kearney (17) 

 places the limit for successful growth between 4000 and 

 6000 parts per million for the white type of alkali. In 

 California the highest alkali in which it was found growing 

 unaffected was 1 260 parts per million total salts, 580 parts 

 per million of sodium carbonate, and 550 parts per million 

 sodium sulphate. 



Brome grass (Bromus inermis) is one of the most resistant 

 of the tame grasses. It has been found (17) to grow un- 



