Fig. 2. The difference over years in annual dry matter yield of selected grasses grown under different soil moisture treatments at Tucumcari, New Mexico. Data are the means of four replications. Bars indicate the LSD (P < 0.05) for within year comparisons. Absence of an LSD within a year indicates no significant difference among soil moisture treatments. Lack of any LSDs within a grass indicates no significant year x soil moisture treatment effect for that grass. Poorly drained, typical irrigation, and winter irrigation signify poorly drained soil irrigated as needed to maintain a moist soil surface, but generally less than once per cutting; furrow irrigated once before each cutting beginning in middle to late April, which is typical to the region because that is when canal water becomes available; and same as typical irrigation, but also irrigated monthly in winter (November to March) using groundwater, respectively.