From early in the morning until late at night, summer sunshine provides the energy trees need to make new wood, twigs, and leaves.
Many tree seeds germinate in summer. Sunlight and moisture send the seed signals to begin to sprout. Water softens the seed shell and expands the food inside. A root grows downward. A stem pushes up toward the sunlight.
Trees grow throughout their lives. They get bigger in three places: root tips, cambium, and buds.
By forming new cells under the bark and at the tips of the branches and roots, a tree grows in diameter and height and extends its root system each year.
Just like people, a tree needs water, nutrients, and energy to grow. A tree draws water and nutrients from the ground through its roots. Like other plants, it uses energy from the sun, captured by chlorophyll and other pigments in the leaves, to transform carbon dioxide and water into sugar. This process, called photosynthesis, takes place in the leaves. The sugar then travels through the branches and trunk to nourish the rest of the tree.