Experimental plots located in the south-central Great Plains USA at the Oklahoma State University Research Range (A) showing grassland site (B), a close-up of a grass tray interceptor (C), open stand site (D), dense stand site showing rain gauges and stemflow collection tanks (E), and closed stand site showing stemflow collector collar (F).

<p>Experimental plots located in the south-central Great Plains USA at the Oklahoma State University Research Range (A) showing grassland site (B), a close-up of a grass tray interceptor (C), open stand site (D), dense stand site showing rain gauges and stemflow collection tanks (E), and closed stand site showing stemflow collector collar (F).