Can a plant grow in ice and snow?It is difficult for plants to survive in the coldest regions of the world, where snow covers the ground for most of the year. In the Arctic tundra that circles the North Pole, once the snow melts in the spring the growing season is short (50 to 60 days), and flowers have little time to make their seeds. Even in the summer it is cold and windy, with just a few months of sunshine. Yet, many different types of plants have adapted to this cold area, where winter temperatures dip below 30 degrees Fahrenheit (34 degrees Celsius) and the average summer temperature is 37 to 54 degrees Fahrenheit (3 to 12 degrees Celsius). In fact, there are about 1,700 kinds of plants in the arctic and subarctic, including low shrubs, sedges, reindeer mosses, liverworts, and grasses; more than 400 types of flowering plants; and lichen. Most plants, such as purple saxifrage, are small, and grow close together and close to the ground. This protects them from the cold temperatures and the strong winds, which can soar up to 100 miles (161 kilometers) per hour. Others, such as the arctic crocus, have fuzzy coverings on the stems, leaves, and buds to protect them from the wind. Plants like the arctic poppy have cup-shaped flowers that face up to the Sun, so the Sun's rays can easily reach the flower's center. These plants stay warmer than the air around them. The Alpine soldanella uses its food stores to keep warm, producing enough “heat” to melt the snow near its roots. Others are dark-colored so the plants can absorb more solar heat. Often, small leaves help the plants retain moisture. Certain plants, such as edelweiss, have a thick coat of hair on them, which traps heat and cuts down water loss. And lichen is super-hardy. It can grow on bare rock and survive long droughts and extremely cold temperatures. |
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