Final answer:
Peat moss is a type of bedding material that expands and changes into a saw-dust consistency when wet.
Step-by-step explanation:
The type of bedding that expands and changes into a saw-dust consistency when wet is called peat moss. Peat moss is a type of bedding material that is commonly used in gardening and horticulture. When it is dry, peat moss is lightweight and spongy in texture.
However, when it gets wet, it expands and turns into a saw-dust like consistency. This property of peat moss makes it ideal for retaining moisture in plant pots and garden beds. It helps to improve water retention and drainage in the soil.
Additionally, peat moss can also be used as a soil amendment to improve soil structure and fertility. Overall, peat moss is a versatile bedding material that undergoes a transformation when wet, making it a useful component in gardening and plant cultivation.