GLBRC Switchgrass Nitrogen-rate Experiment
The Switchgrass Nitrogen/Harvest Experiment is a long-term study located at the KBS GLBRC Intensive Site. The experiment is laid in Randomized Split-Plot design with 8 x 2 factorial arrangements of fertilizer levels and harvest strategies, respectively. Nitrogen applications range from 0 to 196 kg N / ha with two harvest strategies as one and two cuts per year. Plots are 4.5 x 6.0 m (15 x 20’) arranged in each of 4 replicate blocks. The experiment was established in 2008 and the goal is to study the effect of nitrogen levels and harvest strategies on plant productivity, greenhouse gas emissions and nitrogen availability to plants. The first fertilizer application was made after one year of establishment.

In 2012 the experiment was simplified to one harvest per yer but we maintained separate yield values for each subplot.

Lysimeters (soil water samplers) are installed in various plots. Download lysimeter locations.

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