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Eastern redcedar (Juniperus virginiana L.) is rapidly encroaching and degrading native prairie and rangeland landscapes in the Great Plains of the U.S. Little is known concerning the impacts of increasing redcedar density and areal coverage on local and regional water budgets through transpiration (T r ) and canopy interception (C I ) of precipitation. Limited T r and C I studies have been conducted in dense stands of redcedar but results from these studies may not be applicable to redcedar growing in open environments. Four redcedar trees (two large, two small) were located in central Oklahoma to measure T r . Two limbs (one on the north face and one on the south face) on each of the large trees were instrumented with sapflux sensors to measure T r from August 2010 through mid-July 2012. Limb level T r was scaled to tree level T r using ratios of both leaf and bole areas. Whole tree T r was measured on two small redcedar trees from mid-May 2011 through mid-July 2012. Transpiration of the small redcedars was found to respond quickly to precipitation events, while the large redcedars did not. Redcedar T r was compared to that of native grasses. The large redcedars exhibited higher T r rates than native grasses while the small redcedars transpired at rates closely matching native grasses. Four different redcedars were instrumented to measure C I from October 2009 through mid-July of 2012. Redcedar canopies were found to intercept 100% of precipitation for events ≤ 2.4 mm. Redcedar canopies reduce annual precipitation received at the surface by about 33%, and as much as 39% in the western portion of the state. Significant canopy interception of precipitation, coupled with T r rates as large as or larger than native grasses and with year-round T r , suggests increases in redcedar density and areal coverage could affect local water resources (e.g. reducing infiltration, runoff, and ground water recharge rates).

Canopy reflectance (i.e., remotely sensed) data may allow rapid assessment of nutritive values, such as total N, neutral detergent fiber (NDF), and acid detergent fiber (ADF), as well as nutritive quality indicators such as relative feed value (RFV) and a forage energy/protein ratio of alfalfa (Medicago sativa L.). Remotely sensed data were acquired over seven alfalfa cultivars in the 2005 to 2008 growing seasons (n = 580) to develop and test calibration equations to predict concentrations of total N, NDF, and ADF. About 31% of the canopy reflectance dataset and corresponding measured values of total N, NDF, and ADF were used in calibration equation development while the remaining samples (69%) were used to validate the calibration equations. The remote sensing based values of NDF, ADF, and crude protein (CP = total N × 6.25) were used to calculate RFV and the total digestible nutrients/crude protein (TDN/CP) ratio. Measured total N, NDF, ADF, RFV, and the TDN/CP ratio were used to assess the accuracy of the corresponding predicted values from the remotely sensed canopy reflectance data. The remotely sensed based prediction equations explained from 78 to 83% of the variation in measured total N, NDF, and ADF, correctly predicted about 80% of the RFV‐based hay grade classifications, and about 78% of the measured TDN/CP ratios. This technology could help improve profit margins by timing the cutting or harvesting of alfalfa, in rapid assessment of nutritive values over large areas devoted to growing alfalfa, and assessing nutritive quality in real time.