The phenotypic variation of 10 important botanical traits and 2 traits related to herbage quality was measured in tall wheatgrass (Thinopyrum elongatum) cv. Tyrrell. Five certified lines of Tyrrell were compared among themselves and with cvv. Largo and San Jose. Significant differences, both between cultivars and within lines of Tyrrell, were observed for several traits. The phenotypic variability measured confirms that Tyrrell is distinct from its progenitor, Largo, and has sufficient variability to make it suitable for use in a selection program. In a second experiment, from November 1990 to February 1993, the yield and nutritive value of Tyrrell, Largo, and San Jose were compared with perennial ryegrass (Lolium perenne) cv. Ellett and tall fescue (Festuca arundinacea) cv. Demeter. There were no differences (P>0.05) between cultivars for either total dry matter yield or total yield of digestible dry matter. Seasonal differences in growth and nutritive value were observed. Ellett showed superior growth in winter and early spring, while tall wheatgrass and Demeter were more summer-active. In 6 of the 11 harvests measured for nutritive value, there were no differences (P>0.05) between treatments for yield of digestible dry matter; for 2 of the remaining 5 harvests, Tyrrell yielded more digestible dry matter than Ellett. Dry matter digestibility of tall wheatgrass did not fall below 60%. The results suggest that with appropriate management, tall wheatgrass can produce nutritious forage in quantities sufficient for animal production systems, particularly as a special purpose summer pasture.

This work presents a linear smoothing scheme over high-order triangular elements in the framework of a cell-based strain smoothed finite element method for two-dimensional nonlinear problems. The main idea behind the proposed linear smoothing scheme for strain-smoothed finite element method (S-FEM) is no subdivision of finite element cells to sub-cells while the classical S-FEM needs sub-cells. Since the linear smoothing function is employed, S-FEM is able to use quadratic triangular or quadrilateral elements. The modified smoothed matrix obtained node-wise is evaluated. In the same manner with the computation of the strain-displacement matrix, the smoothed stiffness matrix and deformation graident are obtained over smoothing domains. A series of benchmark tests are investigated to demonstrate validity and stability of the proposed scheme. The validity and accuracy are confirmed by comparing the obtained numerical results with the standard FEM using 2nd-order triangular element and the exact solutions.