Trees can be killed by girdling—the removal of bark and vascular cambium in a ring all the way around the tree. Explain why.

Verified step by step guidance

1. Step 1: Understand the structure of a tree. The outermost layer is the bark, which protects the tree. Just beneath the bark is the vascular cambium, a layer of cells that divide to produce new xylem and phloem cells. Xylem transports water and nutrients from the roots to the rest of the tree, while phloem transports sugars produced by photosynthesis from the leaves to the rest of the tree.
2. Step 2: Understand the process of girdling. Girdling involves removing a ring of bark and vascular cambium from around the entire circumference of the tree. This disrupts the tree's vascular system.
3. Step 3: Understand the consequences of girdling. When the vascular cambium is removed, the tree can no longer produce new xylem and phloem cells in that area. This means that water and nutrients cannot be transported from the roots to the upper parts of the tree, and sugars cannot be transported from the leaves to the rest of the tree.
4. Step 4: Understand the impact on the tree's survival. Without the ability to transport water, nutrients, and sugars, the tree cannot survive. The parts of the tree above the girdle will die from lack of nutrients and water, and the roots will die from lack of sugars.
5. Step 5: Summarize the explanation. Girdling kills trees because it disrupts the tree's vascular system, preventing the transport of water, nutrients, and sugars, which are essential for the tree's survival.

Key Concepts

Vascular Cambium

The vascular cambium is a layer of tissue in plants that is responsible for secondary growth, producing new xylem (wood) and phloem (bark). It is crucial for the transport of water, nutrients, and sugars throughout the tree. When girdling occurs, the vascular cambium is damaged, disrupting these essential functions and ultimately leading to the tree's death.

Bark Function

Bark serves as a protective outer layer for trees, safeguarding against physical damage and pathogens. It also plays a role in the transport of nutrients and water through the phloem. Removing the bark in a girdle cuts off this protective barrier and the phloem's ability to transport sugars from the leaves to the roots, which is vital for the tree's survival.

Photosynthesis and Nutrient Transport

Photosynthesis is the process by which trees convert sunlight into energy, producing glucose that fuels their growth. The sugars produced in the leaves are transported down through the phloem to the roots and other parts of the tree. Girdling interrupts this transport system, leading to a depletion of energy resources in the roots, which can cause the tree to die.