Grass Seed Production on Irrigated Land 



By Harry F. 6m an, (farm superintendent, and Russell H. Stark/wm rsery manager; 

 Aberdeen, Idaho, Nursery Unit; Soil Conservation Service 



Grass seed is a new high-income cash crop in many irrigated areas. Grass 

 can replace an annual row crop or a close-growing crop such as grain. 



Irrigated land use in the West is based largely on an annual cash crop. 

 Results of this practice are : ( 1 ) Decrease in soil fertility, ( 2 ) breakdown 

 of soil structure, (3) decrease in water penetration, (4) increase in erosion, 

 and (5) reduction in quality and yield of crop. 



But grass, since it is a perennial crop, increases the organic matter in the 

 soil, causing an increase in fertility and a decrease in erosion. The grass 

 roots improve soil structure, which permits more rapid penetration of water. 

 In addition, grass usually requires less irrigation water after the stand is 

 established than the ordinary annual row crop. It also provides supple- 

 mental feed, such as straw or aftermath grazing. Grass has a low labor 

 requirement and the harvest occurs during favorable weather periods. 



Grass as a cash crop provides better land use than do annual crops. The 

 manner in which the grass fits into a rotation depends upon the type of 

 farming operations that you use. The following rotations are examples of 

 possible ways that you may fit grass seed production into your rotation. If 

 you are interested in livestock production, you will find rotation 2 better 

 than rotation 1. 



Rotation 1 : 



Year 

 1 

 2 

 3 

 4 

 5,6,7 



Crop 

 Establish red clover. 

 Red clover seed. 

 Annual row crop. 

 Establish grass. 

 Grass seed. 



Rotation 2 



Year 



1 



2, 

 5 

 6 

 7, 



3,4 



Crop 

 Establish hay seeding. 

 Hay. 



Annual row crop. 

 Establish grass. 

 Grass seed. 



Grain is commonly seeded as a companion crop in establishing red clover 

 and alfalfa for hay. (A companion crop is often referred to as a "nurse 

 crop." A belter term in most instances would be "wicked-uncle crop" 

 as it often causes more harm than good to a new seeding.) You may find 

 some advantage in seeding red clover or alfalfa after the removal of an 

 early grain crop. Since grain competes directly with grass during the 

 establishment period of the grass, you cannot expect to establish a grass 

 stand that will be successful for seed production where a companion crop 

 is used. Such seedings produce weak grass plants and allow excessive 

 weed growth that depresses the grass growth. The grain stubble seriously 

 hinders cultivation of the grass stand. 



It is impossible to predict seed yields except on a relative basis. Most 

 grasses require high soil fertility for high seed yields. Seasonal weather 

 conditions, especially extremes of high or low temperatures during the 

 blooming period, reduce yields. When and how you irrigate and cultivate 

 influences yields (fig. 1). 



If you are a new grower, confine yourself to the production of one kind 

 of grass. This helps you to prevent mechanical mixtures and also allows 



