A plate meter inadequately estimated herbage mass in a semi-arid grassland

Jeffrey Fehmi, J. M. Stevens

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

A resting plate meter was tested in the laboratory and on a field site to determine its effectiveness for estimating peak herbage mass on semi-arid grasslands. In laboratory tests, data from the plate meter closely predicted the herbage mass of four perennial bunch grasses (thirteen of sixteen tests with r2 ≥ 0·90) but the closeness of the prediction varied with the pressure of the plate. Field tests took place on a southern Arizona, USA semi-arid grassland in 2005, 2006, 2007 and 2008. Twenty teams of two or three people sampled the site; five teams in each year measured eight to thirteen plate heights and clipped the vegetation beneath. Consistent with a need for yearly calibration, a significantly different (P < 0·05) linear relationship was detected between 3 of the 4 years which was associated with differences in average herbage mass of dry matter (DM) (1525 kg ha-1 for 2005, 2093 kg ha-1 for 2006, 1338 kg ha-1 for 2007 and 1370 kg ha-1 for 2008). Plate height poorly predicted herbage mass within years (r2 = 0·21, 0·51, 0·49 and 0·41 respectively) with plate heights explaining half or less of the variability in field herbage mass and having a mean prediction error of 466 kg DM ha-1. The plate meter technique had limited potential for estimating peak herbage mass in semi-arid grasslands.

Original languageEnglish (US)
Pages (from-to)322-327
Number of pages6
JournalGrass and Forage Science
Volume64
Issue number3
DOIs
StatePublished - Sep 2009

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grasslands
grassland
forage
dry matter
prediction
calibration
testing
grass
grasses
vegetation
test
methodology

Keywords

  • Eragrostis lehmanniana
  • Forage estimation
  • Inventory and monitoring
  • Lehmann lovegrass

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Management, Monitoring, Policy and Law

Cite this

A plate meter inadequately estimated herbage mass in a semi-arid grassland. / Fehmi, Jeffrey; Stevens, J. M.

In: Grass and Forage Science, Vol. 64, No. 3, 09.2009, p. 322-327.

Research output: Contribution to journalArticle

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