Observations on the percent cover and forage production of ground vegetation under four years old plantation showed that Eucalyptus camaldulensis, Acacia nilotica and Leucaena leucocephala have a higher allelopathic effect on the growth of grasses under them as compared to Zizyphus mauritiana, Acacia modesta, Dalbergia sissoo and Albizzia lebbek. The cover percent of the vegetation was lowest (8.25%) under Eucalyptus camaldulensis and highest under Zizyphus mauritiana (83%). The cover percent under Acacea midesta and L.leucocephala was 64, 60, 53, 29, and 16%respectively. The forage production data also showed the same trend. It was 4675, 4050, 3200, 2450, 1775, 775 and 662 kg per gertare in the plots planted with Z.mauritiana, A. midesta, D. sissoo. A. lebbek, A. nilotica. L. leucocephala and E. camaldulensis respectively.