|
1. Flowers unstalked or the female ones with stalks up to 1 mm long, usually in pairs at each node; stems over over 2 mm thick and at least 3 cm long; plants parasitic on many genera of Pinaceae................. Arceuthobium campylopodium 1. Flowers terminal on short lateral branches, the branches bearing the male flowers often more than 2 per node; stems scarcely as much as 2 mm thick and usually less than 3 cm long; plants parasitic on Pinus or Pseudotsuga. 2. Secondary branches of twigs lying in the same plane, thus flat and fanlike; stems scarcely 1 mm thick; plants parasitic on Pseudotsuga......................Arceuthobium douglasii 2. Secondary branches of twigs distinctly whorled, not fanlike; stems over 1 mm thick; plants parasitic on Pinus...............................Arceuthobium americanum |
|
