OBJECTIVE FORESTRY

Detailed explanation-1: -The uppermost horizon is called the topsoil layer. The topsoil layer is a mixture of sand, silt, clay and broken down organic matter, called humus.

Detailed explanation-2: -The uppermost layer of the soil is called topsoil and this layer contains humus, plant roots, and living creatures. The more humus found in topsoil, the more nutrient rich the topsoil and the better the conditions for growing plants.

Detailed explanation-3: -Silt is not visible to the naked eye and increases the water holding capacity of soil. Clay has a high surface area, high water holding capacity, many small pores, and possesses charged surfaces to attract and hold nutrients. Figure 2. Relative size comparison between sand, silt, and clay of the fine earth fraction.