The increase in girth, also known as secondary growth, is another important aspect of plant growth and development. Unlike primary growth, which increases the length of the plant, secondary growth thickens the roots and stems.
- This growth is largely attributed to the activity of the vascular cambium and cork cambium.
- The vascular cambium produces new layers of xylem and phloem, which are essential for water and nutrient transport.
- The cork cambium produces cork, which forms the bark, protecting the plant from damage and disease.
Together, these layers not only support the plant structurally but also help it transport nutrients more efficiently, aiding in its overall health and longevity.
This increase in girth is particularly noticeable in woody plants, such as trees and shrubs, where it allows them to grow taller and support more branches and leaves, thereby increasing their ability to capture sunlight for photosynthesis.