Question
I have a couple of res tips trees in my yard and they have developed a fungi on their leaves (it cause the leaves to becomes spotty and fall off...what can I do?

Answer
Hi Janice,

I apologize for not answering sooner; there has been illness in the family, and I have fallen behind.

Keep your Red Tips "blighting-out" by continuing a spring fungicide application program for Entomosporium leaf spot. This disease, also referred to as photinia leaf spot, is the number one problem for Red Tips.

Photinia leaf spot is caused by a fungus which starts its disease cycle early in the year. So practicing preventive medicine before new growth becomes infected is the way to handle this problem. Don't wait until have become heavily blighted before beginning a control program!

Photinia leaf spot shows up as small, circular, bright red spots on upper and lower surfaces of young expanding leaves. These are the first symptoms of the disease. As the disease progresses, the spots merge and blighted leaves often fall from plants. Badly infected photinias usually suffer extensive defoliation and, as a result, don't grow very well. Plus the disease detracts from the appearance of plants.

A good way to control the disease is to rake and destroy diseased foliage from last season. This practice is an essential part of the control program since it removes one of the main sources of fungus inoculum.

Fungicide sprays are also generally necessary in a control program for this disease. Best control of photinia leaf spot is obtained with preventive sprays timed from bud break and applied every ten to fourteen days until all foliage has matured. Mature foliage is no longer susceptible to infection. Provided applications are made on schedule, plants should not be affected by leaf spot.

Fungicides that will do a good job of handling photinia leaf spot include formulations of chlorothalonil such as Spectracide Immunex Multi-Purpose Fungicide, formulations of chlorothalonil such as Dragon Daconil 2787, Ortho Multi-Purpose Fungicide Daconil 2787, Security Fungi-Gard, Black Leaf Lawn and Garden Fungicide, Pennington's Pride Multi-Purpose Fungicide, as well as formulations of mancozeb. A commonly available brand of this latter fungicide is Dragon Lawn and Vegetable Disease Control.

Consult your local garden center to see which of these might be available in your area as local regulations vary.