Answer: From your description, it sounds like a fungal disease. But, without actually seeing the plant I can't positively diagnose the problem. Black Eyed Susan vines grow best in full sunshine, in rich, moist soil. They need lots of air circulation to keep the plants healthy. You might want to take a sample of the affected leaves to your local Cooperative Extension office or Master Gardener Clinic for a positive identification of the problem plus recommended solutions. Best wishes with your garden!
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