Answer: Your winter temperatures a just a tad too cold for Pyrus kawakami to retain its leaves all winter long. The tree will survive, but will not be evergreen. A substitute might be Drimys winteri (Winter's Bark), Osmanthus fragrans (Sweet Olive), Arbutus unedo (Strawberry Tree), or Eriobotrya japonica (Loquat). These trees are more adapted to your winter cold and will remain evergreen.
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