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summary of this information is listed on Table 7, Vegetative Cover Summary of <br />Moderately Tolerant and Moderately Sensitive Species. The particular <br />categories of moderately sensitive and moderately tolerant are based on the <br />article "Crop Salt Tolerance -Current Assessment" by Maas and Hoffman (1977), <br />as referenced in Rule 2.06.8(5)(C)(i)(A). <br />As stated in the referenced article, a species which is considered moderately <br />sensitive may expect same decrease in yield when the soil salinity, measured <br />as ECe, is in excess of 1.5 mmhos/cm. A moderately tolerant species may show <br />~,,,,~eerr115 evidence of decreased yields at an ECe of 3.0 mmhos/cm. Few of the grasses, <br />\`- `i,~~~ ,~A-forbs, and woody plants growing adjacent to the creeks and in the irrigated <br />~~0' , .~"r.,0\Q" pastures have been thoroughly studied; thus, limited information is <br />t available. The article of Maas and Hoffman does report salt tolerance levels <br />ay,y10 ' for some of the genera and species. Orchard grass (Dactvlis alomrata) and <br />a timothy (Phleum pratense) are considered moderately sensitive. Although the <br />species Agrostis palustris, which is considered moderately sensitive, was not <br />found in the area, other species of A rostis located in this region were <br />assumed to be moderately sensitive. Smooth brome (Bromus inermis), mountain <br />broms (Bromus carinatus), reed canarygrass (Phalaris arundinaceae), tall <br />fescue (Festuca elatior which equals F. pratensis), wheat (Triticum <br />aestivum), crested wheatgrass (Agropyron desertorum), and slender wheatgrass <br />(Agropyron trachycaulum), are classified as moderately tolerant. Other <br />species of moderately tolerant grasses include barley (Hordeum vul are) and <br />tall wheatgrass (Agropyron elongatum). It is assumed other species of <br />Hordeum, Agropyron, and Festuca such as foxtail barley (Hordeum <br />brachyantherum), intermediate wheatgrass (Agropyron intermedium), western <br />wheatgrass (Agropyron smithii), wheatgrass (Agropyron), and Idaho fescue <br />(Festuca idahoensis) are moderately tolerant as well. Of the forbs, alfalfa <br />(Medicago sativa) and clover (Trifolium) are considered to be moderately <br />sensitive. For the purpose of this discussion, if a particular species had <br />been classified in terms of salt tolerance, such as Agrostis palustris or <br />Agropyron elongatum, then other similar species were rated within the <br />respective category. An example would be rating Agrostis (species) as <br />moderately sensitive or Agropyron intermedium as moderately tolerant. None <br />of the grasslike plants or shrubs encountered in the area studied were rated <br />for salt tolerance in the article of Maas and Hoffman. • <br />4 <br />Revised 10/1/86 <br />