Betula cordifolia mature to about 3–5 cm long and bear winged nutlets about 2–3 mm long. "Betula cordifolia" is found in Atlantic Canada, Quebec, northwestern Ontario, Northern New York State, and New England. It is generally found in northern habitats or high elevations, particularly on moist ground. "Betula cordifolia" and "Betula papyrifera" are very similar species, indeed they were once considered the same species. The primary methods of distinguishing the one from the other include: Since many of these characteristics vary from tree to tree, ideally several of these characteristics should be noted before making a positive identification. It has been suggested
Citrus gummy bark viroid Citrus gummy bark viroid The citrus gummy bark viroid (abbreviated CGBVd) is a sub-species of the hop stunt viroid, and thus is a member of the genus Hostuviroid. As the name suggests, the citrus gummy bark viroid causes problems in the bark of the sweet orange tree. Scrapping the bark exposes localized spots or a line of reddish-brown, gum-impregnated tissue around the scion circumference especially visible near the bud union. The discoloration and gumming may extend above the bud union to the main branches of the sweet orange while in severe infection dark streaks of gum-impregnated tissue may also be