We examined changes in a community of seedlings/saplings 10–150 cm tall associated with the presence of a widely invasive plant, Lantana camara and environmental covariates along 67 randomly located transects, in Mudumalai, India. We compared plant species assemblage and grass cover in L. camara-invaded and uninvaded plots in three habitats. Multivariate analyses revealed a significant association of all environmental covariates with plant species assemblage. Pairwise tests indicated that L. camara was significantly associated with changes in plant species assemblage and grass cover within the moist and dry deciduous forest, but not in the thorn forest. The relationship between L. camara and that of elephant browse plants varied with species. A linear regression analysis indicated that L. camara invasion was the only significant predictor of grass occupancy. Our results indicate that in addition to other factors, L. camara was associated with altering plant species assemblage, some elephant browse plants and grass cover in the moist and dry deciduous forest. It appears that L. camara can have a major effect on diversity within this reserve, but whether this effect is by L. camara driving the change or being associated with other habitat change requires further experimental evidence.