Agronomy Degree Practice Exam

Which type of soil amendment is typically used to improve drainage?

1. Compost

2. Sand

3. Clay

4. Peat

The correct answer is: Sand

The amendment that is typically used to improve drainage is sand. Adding sand to soil can help increase its porosity and reduce compaction, which allows water to flow through the soil more easily. This is particularly beneficial in heavy, clay-rich soils that retain too much moisture, leading to poor drainage and potential root problems for plants. By mixing in sand, the soil structure is improved, leading to better aeration and allowing excess water to drain away effectively, thus creating a more suitable environment for root growth and overall plant health. Compost, while beneficial for improving soil fertility and structure, does not inherently improve drainage to the same extent as sand. Clay tends to hold water and can exacerbate drainage issues, and peat, although it improves soil moisture retention, can also retain too much water in certain contexts, making it less ideal for enhancing drainage.