I have noticed the surfaces of all plants, shrubs, large rocks used in our landscaping, and even the asphalt driveway (which are under some large trees near our pond) are coated with some dark, sticky material. It looks like it could be some kind of mold. We did have a wet spring here in Hickory, NC, but have not had significant rain in a while. It almost looks like it may have been sprayed with some type of oil, and it is obvious when we come in the driveway, as those areas are very dark. I am positive that no one sprayed anything. Can you advise?
Certified GKH Gardening Expert
This is sooty mold. It happens when a plant gets a pest infestation. The stickiness is from the pests' secretions, called honeydew. It will even "rain" down and cover anything beneath the plants/trees. I would recommend using neem oil on your affected plants, as this will get rid of the sooty mold fungus and kill the pests. On the other areas, you can simply clean well with a solution of diluted bleach.
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