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<br />17 <br /> <br />The forage yields do not show the same trends as the annual crops <br /> <br />~ (Table 6). The yields on the salty plots for irrigation levels 4-6 are <br />~ <br />~ 1.10, 0.95, 0.97, 1.10 times the yields for the fresh plots for alfalfa, <br />CJl <br />wheat grass, mixed grass, and grass alfalfa, respectively. Thus, for all <br /> <br />of the plots as a whole, there was an average 3 percent higher yield on <br /> <br />the salty plots than on the fresh plots. This difference is not statis- <br /> <br />tically significant. However, the ratio of salty/fresh yield on the wheat <br /> <br />grass and mixed grass plots (Figure 6) generally increased with increasing <br /> <br />irrigation level being 0.64, 0.82, 0.97, and 1.08 for irrigation levels <br /> <br />3, 4, 5, and 6, respectively. This effect was not found for the alfalfa <br /> <br />and grass-alfalfa plots (Figure 7) because the ratio of yields of the <br /> <br />salty/fresh plots was 1.21, 1.08, 1.06, and l.l6 for water levels 3, 4, 5, <br /> <br />and 6, respectively. Thus there is a slight trend indicating the saline <br /> <br />irrigation increased yields on any plots with alfalfa in but a reduction <br /> <br /># <br /> <br />of yields for the grass plots especially for low irrigation leyels. <br /> <br />Tables 7 and 8 and Figures A--6 through A-lO show the results of a <br /> <br /> <br />Study of the Field Variability as <br />Related to the Treatments Imposed <br /> <br />study made to determine the field variability in electrical conductivity <br /> <br />(EC) of the 30 cm (1-2 ft) zone. The EC of the salty plots, at water <br /> <br />levels 3 through 6, were'about 4 times that of the fresh water plots. The <br /> <br />data for the salty plots show an effect of the irrigation system with the <br /> <br />highest EC at irrigation levels 3, 4, or 5--the location with irrigation <br /> <br />amounts that are not enough for leaching of salts out of the profile. The <br /> <br />values of EC are lower at level 6 where sufficient water was applied to <br /> <br />leach some salts below the 30 cm layer. The values of EC are lower for <br />