Effect of nighttime warming and nitrogen fertilization (2 g Nm2
yr
1
)on
changes in cover of blue grama (B. gracilis), black grama (B. eriopoda) and C3 shrubs
(e.g., G. sarothrae) during the 2006 growing season based on cover estimates in
February, May and September. Warming significantly increased cover of B. eriopoda
(warming*time F ¼ 7.00, P ¼ 0.003) whereas N addition significantly increased cover of
B. gracilis (time*N F ¼ 5.29, P ¼ 0.016) and marginally significantly increased cover of
G. sarothrae (F ¼ 3.26, P ¼ 0.064) based on repeated measures ANOVA.