Articles submitted by Eddie Ayers, County Extension Agent:Odd Looking Azalea Leaves

This spring I have received several phone calls and looked at several specimens of odd looking azalea leaves. The leaves are suffering from a disease call azalea leaf gall. Azalea leaf gall is a very common and widespread fungus disease that occurs in early spring on new azalea foliage. The leaves become thickened, curled, fleshy and pale green to white in color. Fortunately, this disease is more alarming than damaging.

The problem is caused by the fungus, Exobasidium vaccinii, which is dormant in the developing buds from one year to the next. But when bud growth begins in the spring, the pathogen also renews activity and one or more of the leaves on the shoot may develop symptoms. A spore-bearing tissue is eventually produced which completes its development on exposed leaf surfaces then spores are blown about by air currents. Some of them lodge on the plant and eventually invade leaf buds. The actual damage to plants is not nearly as important as it appears to be. However, if disease is severe, the vigor of the plant can be affected due to the loss of young leaves.

The disease is first noticed soon after leaf buds open in the spring. All or only part of the individual leaf may be affected. Part of the leaf becomes distorted with a pale green to whitish, bladder-like thickening. When young, the thickened, fleshy-like leaf is covered with a white growth. As the galls age they turn brown, dry up and fall to the ground. Occasionally, a black coating may develop on the surface of the gall, particularly during rainy weather, which results from secondary invasion of the galls by the fungus Pestalotia.

By the time you see the swollen leaves, the best control is to handpick or prune out and destroy (burn) galls. If you have had the problem in years past and watch your plants closely in early spring, you can apply a recommended fungicide, such as Daconil 2787 or Mancozeb, but it must be applied in a timely manner. The correct time is just as the buds are breaking from their winter nap.

If you have a serious outbreak in large plantings, you need to spray in early spring when leaf buds just begin to open and at two-week intervals (if spring is relatively dry) through late spring/early summer (mid-June) with a Bordeaux mixture which may reduce the incidence of disease in the following season. Timing of sprays is critical because the spores over-winter in the bark and bud scales.

For more information, contact me at the Gilmer County Extension office.

By: Eddie Ayers, County Extension Agent

I’ve gotten several calls lately about weeds in ponds. Aquatic weeds are undesirable in sport fishing ponds for several reasons. They provide cover for small bream, which results in overcrowding. Weeds also use nutrients and prevent proper bloom development. They can become so abundant that boat traffic or fishing becomes difficult. Extensive weed coverage reduces dissolved oxygen levels during warm, cloudy weather.

In properly constructed ponds, fertilization and liming are often the best controls for rooted aquatic weeds. All green plants must have sunlight to grow; therefore you should not be able to see more than 18” deep in a pond to limit weed growth. This does not mean you need a cloudy pond, but one that has microorganisms growing in the pond. The microorganisms not only block the sun, but they provide food for the fish. When sunlight penetrates more than 18”, the weeds grow and cause problems in the pond. In ponds with shallow edges or excessive water flow, it is difficult to prevent aquatic weed growth. Deepening pond edges and constructing ditches to divert excess water are possible corrective measures.

You can control aquatic weeds temporarily with herbicides. If it is necessary to use herbicides, identify the weed first. Once you have identified the weed, you can select the correct herbicide to control that weed. Follow treatment with a fertilization and liming program to prevent weed reestablishment. Chemical treatments are most effective in the spring when aquatic weeds are actively growing. There is less danger of dissolved oxygen depletions if treatments are done before plant growth covers the entire pond. Summer herbicide treatments often result in oxygen depletion, therefore, treat only a portion of the pond at a time.

Many ponds in Georgia have very soft (low total hardness) water. Adding lime increases fish production and aids bloom development in soft waters. Most ponds need at least one ton of agricultural lime every three to five years. Spread lime throughout the pond; do not pile it in one area. Because most southern soils are deficient in lime, spreading and lightly disking one to three tons of agricultural lime per surface acre over the pond bottom during construction is advisable. It takes about three months for agricultural lime to go into solution.

Builder’s (hydrated) lime can be used to temporarily raise total hardness. It is more soluble than agricultural lime however, it must be added every six to eight weeks to maintain a high total hardness. Apply it at a rate of 50 pounds per surface acre, and use it only when agricultural lime is not practical. WARNING: HYDRATED LIME CAN BE TOXIC TO FISHES. DO NOT EXCEED RECOMMENDED APPLICATION RATES. For more information, contact me at the Gilmer County Extension office.

Also, I want to remind you that the Gilmer County Farmer’s Market sponsored by the Master Gardener Cooperative Extension Volunteers of Gilmer County and the University of Georgia is now under way for the 2015 summer season. The Farmer’s Market promotes local artisans and produce growers. It’s open Saturday mornings through October 3rd on Broad Street in Ellijay, adjacent to the Gilmer County courthouse. The hours are from 8:00 am until 12 noon. If you are planning to visit the market, keep in mind that produce vendors can leave as soon as they sell out, so make sure you arrive early to select from all the choices available. And once again this year, the Master Gardener volunteers have their “Ask a Master Gardener” table set up that will have information about flowers, vegetables, and general gardening. Remember: shop local!!!

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