#rheum nobile

Rheum nobile, aka the Sikkim rhubarb or noble rhubarb, is a giant herbaceous plant native to the Himalaya, from northeastern Afghanistan, east through northern Pakistan and India, Nepal, Sikkim (in India), Bhutan, and Tibet to Myanmar, occurring in the alpine zone at 4000–4800 m altitude.

At 1–2 m tall, it towers above the other shrubs and low herbs in its habitat, and it is visible across valleys a mile away.

R. nobile is often called a glasshouse plant because of its outer curtain of translucent leaves which pass visible light, creating a greenhouse effect, while blocking ultraviolet radiation. These are likely defenses against the increased UV-B exposure and extreme cold in its high altitude range.