Betula grossa Betula grossa Betula grossa, commonly known as Japanese cherry birch, is a species of birch native to Japan, where it grows naturally in mixed woodland on hill and mountain slopes in Honshu, Shikoku , and Kyushu. It was introduced to the West in 1896, but remains rare in cultivation. "Betula grossa" is conical in outline, but its most distinctive feature is its cherry-like bark, with horizontal stripes of reddish-grey becoming dark grey with age, exfoliating in thin papery curls. The dark green leaves are up to 10 cm long and turn golden-yellow in autumn. The shoots are aromatic, and carry
Citrus gummy bark viroid observed in longitudinal sections. 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