A forest is a purifier of air and water.

State the statement true or false:

Excreta of animals pollute the soil.

Solve the following crossword puzzle:

Across
3. Growing trees on a large scale.
4. Branched part of a tree above the stem.
Down
1. It refers to the diverse forms of life on Earth.
2. Roof formed by the branches of tall trees over other small plants.
5. An international organisation for forest conservation.