Betula alleghaniensis to the thin bark and lack of ability to resprout, it is easily killed by wildfire. Sugar maple ("Acer saccharum") exerts allelopathic effects on seedlings of yellow birch and decreases their growth ability. The inhibitory chemical is exuded from the roots of the sugar maple and has a very short soil half-life, it no longer has effects on birch after 5 days. It is listed as endangered in Illinois. Yellow birch is considered the most important species of birch for lumber and an important hardwood timber tree; as such, the wood of "Betula alleghaniensis" is extensively used for flooring, furniture,
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