Answer: Junipers are susceptible to Phomopsis infection, especially if growing conditions are conducive to it. You may find the following information, including a list of resistant junipers, helpful. Please understand that resistant does not mean immune.
Junipers in general are potentially susceptible to spider mites. Here is information about the spider mites on junipers.
Junipers are generally regarded as reliable landscape plants with few serious insect or disease problems, although as with any plant there are potential problems.
If you have had serious problems with pests and diseases in your landscape in the past, I would suggest you work with your local county extension and/or professionally trained and certified nurseryman to identify plants that are suitable to the growing conditions in your landscape, and strategies for limiting potential problems.
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