Infections usually start at the leaf margins and can spread along the veins into the center of the leaf.
Spots are brown and irregular and often appear as discrete spots with yellow halos.
This disease can be minimized by improving air circulation by thinning the plants and by avoiding overhead irrigation. Picking and destroying infected leaves is also helpful. Chemical control is not usually necessary. Insect Problems Asiatic garden beetle, Maladera castanea . The grubs of this imported insect also feed on grass roots and are responsible for considerable injury to lawns.