How Trees Prepare for the Toughest Seasons
In How Trees Prepare for the Toughest Seasons, narrator Sir David Attenborough explains how trees survive harsh winter environments. In northern forests, trees prepare for the cold by pulling water into their trunks and creating a sugary antifreeze. But while most trees lose their leaves, pine trees can survive temperatures as low as -40°F and keep their needles all winter. One special type of pine, the bristlecone, can live for up to 5,000 years, with its cones growing for only six weeks each year. This video is excerpted from BBC's Life, a show that explores the remarkable strategies animals and plants use to ensure their survival.
Lesson Express
Q: What role does chlorophyll play in the survival of trees during the fall and winter?
A: Chlorophyll is the green pigment in leaves that helps with photosynthesis. As winter approaches, trees stop producing chlorophyll, causing their leaves to change color and fall off. This helps trees conserve energy and water, which is essential for surviving the winter months.
Q: How do pine trees differ from other trees in how they handle winter conditions?
A: Unlike other trees that shed their leaves in winter, pine trees keep their needles, which contain antifreeze to survive cold temperatures. This allows them to endure even colder winters, sometimes as low as -40°F, for up to five months.
Q: How is the ability of trees to survive harsh winters similar to or different from how animals prepare for winter?
A: Both trees and animals have adaptations to survive harsh winters, such as storing food or conserving energy. However, while animals might hibernate or grow thicker fur, trees adjust by pulling water back into their trunks and creating antifreeze. Both strategies help protect against freezing temperatures and ensure survival until spring.