Witches' brooms on black spruce caused by Arceuthobium pusillum.
Witches broom on black spruce caused by Arceuthobium pusillum that was in the lab - without needles.
Black spruce showing loss of apical dominance and enlarged side branch that was infected with dwarf mistletoe.
Cross section of a tree with dwarf mistletoe infection. Sinkers of the mistletoe follow the ray parenchyma cells into the wood to absorb nutrients.
Cortical strands and sinkers (yellow cells) of dwarf mistletoe in cross section of conifer branch as seen under the microscope.
Male shoots of Arceuthobium pusillum.
Female shoots of Arceuthobium pusillum.
Seeds, produced in September, on Arceuthobium pusillum.
Basal cups of Arceuthobium pusillum. When the shoots fall of the branch a segment of the dwarf mistletoe shoot remains.
Dwarf mistletoe, Arceuthobium americanum, on Jack pine from Manatoba, Canada.
Dwarf mistletoe on Ponderosa pine growing in northern Arizona.