Tsanzo's village is close to Naisi River.

Many villagers grow crops along the riverbank.

Every year, floods wash away crops.

One day, Tsanzo's teacher explained a natural way to control flooding.

"Do not plant crops along the riverbank. Instead, plant many trees," said teacher.

At home, Tsanzo told his parents about the lesson.

They were not interested, but Tsanzo did not give up.

He collected seeds that fell under trees.

Tsanzo collected 100 waterberry seeds, 100 khanya seeds, and 120 African teak seeds.

He planted the seeds in plastic bags he picked up around the village.

Tsanzo watered the soil daily. Most of the seeds germinated.

Tsanzo watered the seedlings. Soon, 300 saplings were ready to be transplanted along the riverbank.

Tsanzo and the villagers planted two hundred saplings on the first day.

On the second day, they planted the remaining one hundred saplings.

Tsanzo and the village children watered the plants every week.

The trees survived the first rainy season and grew quickly.

The villagers planted crops again.

The rows of trees held the soil together.

They trapped plants and other things carried by flooding water.

The trees protected the villagers' crops.