Acer macrophyllum
In addition to oaks, many other forest species may be hosts for the disease; in fact, it was observed in the United States that nearly all woody plants in some Californian forests were susceptible to "P. ramorum". including rhododendron, madrone ("Arbutus menziesii"), evergreen huckleberry ("Vaccinium ovatum"), California bay laurel ("Umbellularia californica"), buckeye ("Aesculus californica"), bigleaf maple ("Acer macrophyllum"), toyon ("Heteromeles arbutifolia"), manzanita ("Arctostaphylos spp."), coast redwood ("Sequoia sempervirens"), Douglas fir ("Pseudotsuga menziesii"), coffeeberry ("Rhamnus californica"), honeysuckle ("Lonicera hispidula"), and Shreve oak ("Quercus parvula"). "P. ramorum" more commonly causes a less severe disease known as ramorum dieback/leaf blight on these hosts. Characteristic symptoms are dark spots on foliage and in some hosts the dieback of the stems and twigs. The disease is capable of killing some hosts, such as rhododendron, but most survive. Disease progression on these species is not well documented. Redwoods symptoms show purple lesions on sprouts and needle discoloration and cankers on small branches, which can lead to sprout mortality.