Laburnum in "L. anagyroides" and long in "L. alpinum". They have yellow pea-flowers in pendulous leafless racemes long in spring, which makes them very popular garden trees. In "L. anagyroides", the racemes are long, with densely packed flowers; in "L. alpinum" the racemes are long, but with the flowers sparsely along the raceme. The fruit develops as a pod and is extremely poisonous. The yellow flowers are responsible for the old poetic name 'golden chain tree' (also spelled golden chaintree or goldenchain tree). All parts of the plant are poisonous, although mortality is very rare. Symptoms of laburnum poisoning may include
Slice genus Slice genus In mathematics, the slice genus of a smooth knot "K" in "S" (sometimes called its Murasugi genus or 4-ball genus) is the least integer g such that "K" is the boundary of a connected, orientable 2-manifold "S" of genus "g" properly embedded in the 4-ball "D" bounded by "S". More precisely, if "S" is required to be smoothly embedded, then this integer "g" is the "smooth slice genus" of "K" and is often denoted g("K") or g("K"), whereas if "S" is required only to be topologically locally flatly embedded then "g" is the "topologically locally flat slice genus"