The holly is a small tree with leaves. It provides birds with food, and with protection from winter storms and predators. But it does not encourage caterpillars, and with good reason. Certain types of caterpillars attack trees, and strip them of all their leaves for food. However, the leaves of the holly tree are designed in such a way as to prevent such an attack. Caterpillars generally like to eat a leaf from the edge, nibbling inwards, until the entire leaf is consumed.
But the leaves of the holly tree have very thick edges. In fact, the edges are so tough that a caterpillar finds it difficult to get even a nibble. The frustrated caterpillar therefore, will decide it is not worth the trouble, and leave the holly tree alone!
Picture Credit : Google