Graycorrelation analysis on ornamental value of thirteen ornamental grasses during summer and autumn in Nanjing area

Ornamental grass as a new kind of plantdesign materials has great value in the construction of city green spaces and ecological landscape. Ornamental characters of 13 species of ornamental grasses were evaluated using graycorrelation analysis based on the oversummering survive rate, the plant growing situation, ornamental character, inflorescence aesthetic feeling and leaf color. The results showed that seven ornamental grasses, Pennisetum alopecuroides, Imperata cylindrical cv.Red Baron, Phalaris arundinacea var. picta, Cymbopogon citrates, Cortaderia selloana cv.Silver Comet, Carex oshimensis cv.Vergold, Acorus gramineus cv.Ogon, were better in ornamental and landscaping effects as they keep steady ornamental values in summer and autumn. Some ornamental grasses, such as Miscanthus sinensis cv.Zebrinus, Cortaderia selloana, M．sinensis cv.Variegatus, M． Sinensis cv.Gracillimus, have a high ornamental values in autumn since they flower in that season. Festuca ovina var.glauca has a ornamental value in silverblue leaves in the early growing phase. Stipa tenuissima does not adapt to the conditions of Nanjing.