File: dex25.xls


Dex25.xls refers to density data collected during USFS Study FSRM 1706-25 that were not formally included in that study.

The file contains perennial grass, shrub, and forb density data. Density was recorded as number of plants per 100 square ft. The 1974 measurements were taken to show density changes since 1972. The 1975 measurements were taken at locations established in USFS Studies FSRM 1706-09 and 1706-12.

Measurements were taken in the summer on three to ten permanent 1x100-ft. belt transects in selected pastures. In 1974 three transects were measured in pasture 1 and ten transects each in pastures 3, 5N, 5S, 6B, and 12B. In 1975 five transects were measured in pastures 1 and 8; eight in pastures 3, 6B, 12B; and ten in pastures 2N, 5N, and 5S.

During study 1706-25 pastures were grazed either yearlong or according to a Santa Rita three-pasture rotation system.

Pastures were blocked by elevation -- high (1150-1340 m), intermediate (1040-1220 m), or low (880-1040 m).

Mesquite treatments on transects established for earlier studies are coded as follows: DEAD for transects on which mesquite (Prosopis velutina) was killed in Studies 1706-09 and 1706-12, and LIVE for transects on which mesquite was left untreated.

Taxa were recorded separately to the species level in most cases and sometimes to the genus level only. The codes OTHSHRUB and OTHFORB refer to unidentified shrub and forb species. In this file ARIS refers to tall Aristida species (specifically Aristida hamulosa and Aristida ternipes).

Sources of data were the original field data sheets.

A value of -9999 in a field means that no data were available because a reading was not made for that date.



dex25notes.txt
26 October 2001