Answer: It's not clear if you are referring to insects or some type of discoloration/fungus on the foliage, so without knowing more I can't provide a definitive answer. However, often times pests or diseases will target stressed plants, so what we see as the "problem" is actually not the underlying issue. For example, ineffective watering, either over or under, is often the culprit, creating a weakened plant. I suggest you contact your County Cooperative Extension office, 2345 Red Rock St, Las Vegas, 702-223-3130. They have Master Gardeners who can ask you detailed questions, and even look at a sample of the leaves if you bring them in, and get to the root of the matter. Good luck!
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