In the United States, "Phoradendron" are most important in California on incense cedar and true fir in certain areas and important broadly across the Southwest (California to Texas) on junipers. Extensive infections and mortality are uncommon in ashes. However, infections occur typically in open-grown trees. This true mistletoe is used as greenery in Christmas decorations. Many species of hardwood trees are affected by mistletoe, but oaks and hickories are most commonly attacked. The impact of infestation is not normally severe, but the parasite may lower individual branch vigor. Where infestations are severe, tree decline may progress to the point where insect and fungus pests combine to kill trees. Injury caused by dwarf mistletoe is manifested in a variety of ways: reduction in tree growth, distortion of growth, reduction in wood quality, predisposition of trees to secondary attack, and reduction in seed yield.