Answer: Holly is subject to a variety of insects and disease including leaf spots, cankers, bacterial blight, twig die back, spot anthracnose, powdery mildew, leaf miners, mealybug, mites, gypsy moth, nematodes, various scales and many others. Based on your description, it may be a bacterial or fungal disease. Without know for sure what you're dealing with, I can't offer a solution. You might want to take some of the affected leaves to your local nursery or Cooperative Extension office for diagnosis and recommended control measures.
Your magnolia seems to be suffering - perhaps from recent transplant. I'd suggest keeping it well watered (one deep soaking per week) and allowing it to continue getting its root system established. In the spring you can feed your tree to encourage healthy new growth.
Best wishes with your landscape!
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