Estimates of herbaceous standing crop by microdensitometry

R. S. Driscoll; P. O. Currie; M. J. Morris

Treesearch

Estimates of herbaceous standing crop by microdensitometry

Formally Refereed

Authors:

R. S. Driscoll, P. O. Currie, M. J. Morris

Year:

1972

Type:

Paper

Station:

Rocky Mountain Research Station

Source:

In: Proceedings, 38th Annual American Society Photogrammetry Meeting; Washington, D.C.; March 12-17, 1972. Falls Church, VA: American Society Photogrammetry. p. 358-365.

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Abstract

Green standing herbage of seeded big bluegrass (Poa ampla) and corresponding dry weight were each regressed as dependent variables (Y) on color infrared photo image density (X) obtained from two photoscales: 1:563 and 1:3855. Standing crop biomass expressed by the linear equation: Y = a + b(X) was from the 1:563 photoscale. The coefficient of determination r2 = 0.752) between image density and harvested dry weight was highly significant (P = 0.01). The same regression using the smaller photoscale (1:3855), although significant (P = 0.05), was not as good (r2 = 0.639). Mean image density of six simulated productivity levels was significantly different (P = 0.05) among most levels of production represented in both photo scales.

Keywords

herbaceous standing crop, microdensitometry, big bluegrass, Poa ampla, image density, photo scales

Citation

Driscoll, R. S.; Currie, P. O.; Morris, M. J. 1972. Estimates of herbaceous standing crop by microdensitometry. In: Proceedings, 38th Annual American Society Photogrammetry Meeting; Washington, D.C.; March 12-17, 1972. Falls Church, VA: American Society Photogrammetry. p. 358-365.