The technique is not sustainable beyond a certain population density because, without the trees, the soil quality soon becomes too poor to support crops.

While the soil could support other crops, the steep slopes of these areas were better used by vineyards.

In other areas, the salt-saturated land may not support crops for as long as two or three years.

The floor of the canyon appeared extremely fertile, supporting numerous large trees and growing crops.

Crucial for food supply on new colony worlds that won't support crops initially.

Most people who live here were farmers, but the sandy here soil will not support crops.

Governments also have limited discretion to continue to direct a small proportion of the total subsidy to support specific crops.

This is not supporting new crops, but continuing or extending the existing regime.

They soon find that the soil of the rain forests is not rich enough to support crops.

Archaeological investigation has identified evidence of irrigation where the natural rainfall was insufficient to support crops.