Question

Which plant is described by these clues? The Latin name the Romans gave this tree was itself borrowed from a Gaulish word for bitumen, and Pliny records the Gauls boiling tar out of its bark. It is {monoecious} and wholly without a {perianth}, its female flowers massed by the dozen into slim upright green spikes, three of them behind each small scale that hardens into a three-lobed {bract}. Each ripe seed is a papery two-winged disc only about 1/16 to 1/8 inch (2 to 3 mm) long, and the whole seed-spike falls to pieces on the twig, shedding scales and seeds together. Its roots trade sugars underground with fly agaric and a long roster of other partner fungi, which is why red-and-white toadstools so often ring these trunks in autumn. The trunk is chalk-white and lifts away in fine horizontal papery sheets, ruled across with dark raised {lenticels}. Its male tassels are already formed by late summer and stand bare and shut on the shoots through the whole winter, lengthening to shed pollen only in April, as the first leaves break, across its native European range. Young shoots are entirely hairless yet rasp under the fingers, roughened all over by scattered whitish resin warts. The blades are triangular to diamond-shaped, 1 to 3 inches (2.5 to 7 cm) long, drawn out to a long point and sharply double-toothed, turning clear yellow in autumn. A fast, short-lived pioneer of poor sandy and peaty ground, it runs from Iceland east to the Urals and western Siberia and reaches 50 to 80 feet (15 to 25 m). Its species epithet is simply the Latin word for hanging, given for the fine outer twigs that drop almost sheer from the arching ends of the branches. In early spring the trunk is tapped for a watery sap of about one percent sugar, drunk fresh or fermented into wine, while the leafy twigs are bound into besom brooms and into the Finnish sauna whisk called a vihta or vasta. Look for a white-trunked tree whose bark cracks into black diamond-shaped fissures above a rugged blackened base, with hairless warty shoots and the finest twigs falling straight down, while the softly downy, wart-free tree of the wetter ground beside it is a different species altogether.

Accepted Answer

Betula pendula

Name That Plant #102