Forests of Karnataka are primarily deciduous and evergreen. Deciduous forests have preponderance of deciduous trees, whereas evergreen forests are dominated by evergreen trees. Deciduous trees completely shed their leaves for some time during the year; they have a distinct period of leaf lessness ranging from a few days to a few months. In tropical deciduous forests, leaf fall is primarily determined by reduction of water availability in the soil. Evergreen trees also shed their leaves but not all at the same time; they do not become leafless during any part of the year. In the driest parts of Karnataka, as also in the highly degraded forests of the state, there is predominance of thorny species. Appearance of thorny elements is reflective of the nature’s adaptation to harsher conditions, where there is need for conservation of energy and water, besides warding off herbivorous intruders.