Definition: A tundra is a terrestrial biome which includes, across its spatial extent, only low-growing vegetation such as dwarf shrubs, sedges and grasses, mosses, and lichens. Tundra biomes rarely have monthly average temperatures above 10 degrees Celsius and have low evapotranspiration ratios.
Definition: Determined for type of life cycle being annual, binneal, perennial etc.
Comment: The life cycle habit indicates the typical duration of an individual plant's life. Common values are annual, biennial, and perennial. Some plants have different durations depending on environment or location, so a plant can have more than one value.
Definition: Of plant duration, a plant whose life span extends over more than two growing seasons, c.f. annual, biennial, ephemeral, of flowering with respect to architecture, hapaxanthic, monocarpic, pleonanthic