Betula pendula (as "B. oycoviensis") was previously listed on the Red List as vulnerable, though it is now considered a synonym of "Betula pendula" subsp. "pendula". "Betula szaferi" was previously considered extinct in the wild on the Red List, but is now considered a form of "B. pendula" with the presence of a mutant gene, causing it to grow weakly and fruit heavily. Silver birch is often planted in parks and gardens, grown for its white bark and gracefully drooping shoots, sometimes even in warmer-than-optimum places such as Los Angeles and Sydney. In Scandinavia and other regions of northern Europe, it is
Beech bark disease to spread to the south and west. The first case of beech bark disease in the United States was reported in 1929 in Massachusetts. By 2004, the disease had spread as far west as Michigan and as far south as western North Carolina. For beech bark disease to occur, two components are required, an insect and a fungus. The beech scale insect, "Cryptococcus fagisuga", is invasive to North America and is host-specific, feeding exclusively on beech trees. It can be observed on the trunk and limbs of the tree as woolly, white tufts that will later develop into broad strips.