## 2 Methods
### Flights and Ground Support  
FLEX-US airborne flights were flown over the Parker Tract site from September-October 2013. For the science flights, the nominal flight altitude was 600 m above ground level (AGL) with instrument FOV ranging from 35\({}^{\circ}\) to 60\({}^{\circ}\) and native ground sampling of 2 m. Flight profiles per observation period consisted of 8 N-S lines (shown in red, Figure 1) with 50% overlap to achieve high density mapping of a 12.5 km\({}^{2}\) area within the boundary of the LP plantation. One of the eight flight lines that covered the area to be mosaicked also passed over the AmeriFlux NC2 flux tower (Figure 1). In addition to the N-S lines, two more flight lines at the beginning and conclusion of each collection (shown as yellow lines in Figure 1, totaling ten lines per measurement period) were flown in the solar principal plane (SPP) and also passed over the NC2 tower. Each collection of the 10 flight line pattern took -45 min. Reported here are results from data collected with this pattern, repeated 4 times over a diurnal cycle, yielding morning (10:30 local time, 55\({}^{\circ}\) to 62\({}^{\circ}\) solar zenith angle, SZA), mid-day (13:15 local time, 48.5\({}^{\circ}\) to 50.9\({}^{\circ}\) SZA) and afternoon acquisitions (14:15 local time, 49.6\({}^{\circ}\) to 56.5\({}^{\circ}\) SZA; and 15:45 local time, 60\({}^{\circ}\) to 66.9\({}^{\circ}\) SZA) over two consecutive days (26-27 October). Ground based support included the AmeriFlux tower and related meteorological information gained from the instrumented tower (e.g., air temperature) located within the most mature LP stand. A ground-based Fieldspec-4 VSWIR spectroradiometer (ASD, Inc., Boulder, CO, USA) was positioned over two m\({}^{2}\) calibration tarps (20% and 5% reflectance) laid out on an open grassland field (lat. 35.873635, long. \(-\)76.658774), and paired with a multiband photometer (CE318-T, Cimel Electronic, Paris, France) to record the atmospheric transmissivity, for use in atmospheric corrections of the optical data. Ground-based optical data were collected continuously throughout the days (09:00 to 17:00) when flights occurred for calibration and validation purposes on the grounds of the NC Department of Agriculture Tidewater Research Station. The two calibration tarps were spread out on a lawn and ASD measurements of the reflected radiances were made during the flights over the tarps, along transects (lengths, 2\(\times\) the width of the tarps) across the lawn, and across a nearby parking lot at 1 m intervals. A second ASD spectroradiometer made measurements of a white Spectralon calibration panel (Labsphere Inc., North Sutton, NH, USA) at 10 s intervals. The calibration panel was also measured with the spectroradiometer used for the tarp measurements after each measurement set, to enable cross-referencing. These two ASDs were also cross-calibrated in the laboratory before and after the campaign. Surface temperatures were collected using a thermal gun (model 100L-LV, Everest Interscience, Inc., Chino Hills, CA, USA) in conjunction with the ASD measurements. Surface temperatures were also measured at a nearby pond. A hand held IRT device (Agri-Therm II, Everest Intersciences, Tucson, AZ, USA) and a portable calibration black body ([PERSON], Asheville, NC, USA) were used to measure the temperature of selected ground targets to verify the accuracy of G-LiHT's surface temperature products. Leaf area index (LAI) was measured using a LAI-2000 Plant Canopy Analyzer (Licor Inc., Lincoln, NE, USA) at 37 plots spanning a range of stands of known age, where measurements were taken along two 10 m transects (NE\(\rightarrow\)SW, NW\(\rightarrow\)SE). Within 1/10 are plots, average tree height was determined using clinometers, tree diameter was measured at breast height (DBH at 1.30 m), and forest stand density with stem counts (Table 1).