A study was undertaken at the Prabhunagar Forest Farm of the University of Agricultural Sciences, Dharwad, Karnataka during 1985 and 1986 to study the growth of natural grass underneath different forest tree species like Leucaena leucocephala, Eucalyptus tereticornis, Casuarina equisetifolia, Acacia auriculiformis, Albizia molucana, Dalbergia latifolia, Dalbergia sissoo, Tectona grandis and Quercus sp. The results on green matter yield revealed that there was significant effect due to different tree plantations on the natural grass grown beneath the trees. In general/all the plantations suppressed the growth of grass. However, L. leucocephala permitted better growth of green grass (82.3 q/ha). Next in order was Quercus sp. (71.7 q/ha). Minimum growth was observed under E. tereticornis (46.5 q/ha) and A. auriculiformis (46.7 q/ha). The yield of grass under no plantation (Check) was highest (124.7 q/ha)