Every year a fungus disease called Entomosporium leaf spot (Entomosporium maculatum) causes some damage in a number of common landscape plants. Because the disease is favored by wet weather, it's been more troublesome this year, and is likely to get worse as our rainy weather continues.

Many people are familiar with the leaf spot because so many common plants are affected. Susceptible plants include Indian hawthorn, pyracantha, pear, flowering pear, flowering quince, cotoneaster, loquat, apple and photinia. The spots first appear as small reddish dots on either surface of young leaves. Often the spots are surrounded by a yellow "halo." You will begin to notice the spots about now, as new leaves begin to emerge. As the leaves age, the spots become darker and larger.

The disease is spread by spores which wash onto uninfected leaves from infected ones. Rain or sprinkler irrigation effectively spreads the disease. Infected leaves often fall off the plant, and if the infection is severe enough, the entire plant may defoliate. Plants are rarely killed, but they can become very unsightly.

Old infected leaves are the main source of spores, so removing old infected leaves is one way to control the disease. Pick spotted leaves off plants, and rake up and dispose of any leaves that have fallen to the ground. Toss the old leaves into the garbage can, or thoroughly compost them.

One of the main ways of preventing the disease in susceptible shrubs is to avoid overhead watering. Also, plant shrubs with adequate spacing to allow good air flow to speed drying of the foliage and to reduce the humidity. The disease is arrested by dry weather, so unless you are sprinkling the foliage, the spotting will only be a problem from late winter to early spring. If you believe the problem is severe enough to warrant chemical control, fungicides can be used to prevent infections on new growth. By early summer, all you should see are spots on the old foliage.