Agrostis ~-a lust-ri~s or A ro ron elongatum, then other similar genera
<br />were rated wit~Fin the respective category. An example would be rating
<br />A r~ostis (species) as moderately sensitive or A rg~yron intermedium as
<br />mo erately tolerant. None of the grasslike plants or- s ru s encountered in
<br />the area studied were rated for salt tolerance in the article of Maas and
<br />Hoffman,
<br />The specific region of the Foidel Creek alluvial valley floor which was
<br />sampled is located approximately 2200 feet from the confluence of Middle and
<br />Foidel Creeks, and is noted as Pasture 19 on Map 1. The area covers 10.1
<br />acres. Data from five transects were collected. The species and their
<br />respective cover and composition is reported on Table 1. The total
<br />vegetative cover is 85.6%. Of that amount, grasses comprise 40.4%, grasslike
<br />plants, such as Carex and Juncus, cover 12.0%, forbs are 27.4%, and
<br />shrubs cover 5.8°k--Ttegarding ~t tolerance, 5.8% of the grasses are
<br />considered moderately tolerant (slender wheatgrass and mountain brome) and an
<br />additional 7.6% are of similar genera are considered moderately tolerant
<br />(intermediate wheatgrass, western wheatgrass, foxtail barley). Thus, a
<br />total of 13.4% of the species can be considered moderately tolerant. Timothy
<br />is described as moderately sensitive and covers 3.0% of the area. Bentgrass,
<br />1.6°6, is of similar genera which is considered to be moderately sensitive.
<br />Thus, a total of about 4.6% of the plant species can be considered moderately
<br />sensitive.
<br />The area which was sampled for the Middle Creek alluvial valley floor is
<br />shown on Map 1 as the irrigated pastures 7, 2, and 8S. The native vegetation
<br />in region 18 was included in the summary analysis. A total of 36 transects
<br />were conducted. The individual species cover and their composition is
<br />reported on Table 2, Middle Creek Alluvial Valley Floor. The total
<br />vegetative cover is 76.7%, Grasses comprise 53.3%, grasslike plants cover
<br />9.2%, forbs cover 13.3%, and shrubs cover .9%. Of the grasses, slender
<br />wheatgrass, mountain brome, smooth brome and tall fescue are considered
<br />moderately tolerant. Similar species of other tolerant grasses include
<br />intermediate wheatgrass, western wheatgrass, wheatgrass, Idaho fescue, and
<br />foxtail barley. Using the weighted averages as calculated for the study
<br />area, shown on table 5, the moderately tolerant species cover 26.8% of the
<br />area. Moderately sensitive grass species (orchard grass and timothy) are
<br />found in the Middle Creek region. Bentgrass and white Dutch clover
<br />(Trifolium repens), which are considered to be moderately sensitive, are
<br />also found. On a weighted average, a total of 14.5% of the Middle Creek
<br />sample area is composed of moderately sensitive species.
<br />The Trout Creek alluvial va]ley floor region was evaluated with the
<br />assessment of irrigated pastures 7, 8, 10, 11, 12E, 14, 15N, and 15S which
<br />are denoted on Map 1. Pasture 12W was also sampled; this pasture has been
<br />irrigated in the past, but is not currently used for hay production. The
<br />area is more typical of a sagebrush/meadow type community. Data from a total
<br />of 36 transects was collected in this area. Table 3, Trout Creek Alluvial
<br />Valley Floor, shows the individual species' cover and composition. In this
<br />region, total vegetative cover is 80.6%. The grasses cover 50.8%, grasslike
<br />plants cover 6.2%, forbs comprise 22.4%, and shrubs cover 1.2% of the area.
<br />Smooth brome and reed canarygrass are both considered moderately tolerant.
<br />Similar moderately tolerant species include tall fescue (Festuca
<br />arundinaceae), foxtail barley, intermediate wheatgrass, western wheatgrass,
<br />and wheatgrass. A total of 16.1% of the area is composed of moderately
<br />tolerant species, as calculated on a weighted average. Orchard grass and
<br />2
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