Questions: How Seasons Affect Plants

Question 1

Why do many trees drop their leaves in autumn?

• A. The leaves are too heavy for the tree to hold
• B. Dropping leaves helps the tree save water and energy during the cold winter when there is less sunlight for growth
• C. The wind blows the leaves off
• D. The tree does not need leaves anymore because it is finished growing forever

Answer: (B)

Trees use their leaves to capture sunlight and make food. In winter, there is less sunlight and it is harder for leaves to do their job. Keeping leaves would also waste water. By dropping its leaves, the tree goes into a resting state (dormancy) to survive the cold, dark winter. When spring brings warmth and longer days, the tree grows new leaves and starts again.

Question 2

A tree that has lost most its leaves in winter is dead.

• T. True
• F. False

Answer: False

A leafless tree in winter is dormant -- alive but resting. If you look closely, you can see buds on the branches that will open into new leaves in spring. The trunk, branches, and roots are all still alive. Dormancy is a survival strategy, not death.

Question 3

How can you tell that a tree is still alive in winter even though it has no leaves?

Model answer: You can look for buds on the branches -- small bumps where new leaves will grow in spring. You can also scratch a small part of a twig and see green living tissue underneath the bark. The trunk and roots are alive even though the tree looks bare.

Dormancy can look like death to an untrained eye. Learning to spot signs of life in a dormant tree -- buds, green tissue under bark -- builds observational skills and reinforces that dormancy is a temporary resting state.