Soil Science Agricultural Chemistry

According to the USDA (United States Department of Agriculture) soil classification, the particle size for medium sand ranges from 0.25 mm to 0.50 mm. This size is coarser than fine sand (0.05 - 0.25 mm) and finer than coarse sand (0.50 - 1.00 mm). Hence, 0.50 - 0.25 mm falls within the correct range for medium sand.

Legume crops (such as beans, lentils, and peas) have symbiotic relationships with nitrogen-fixing bacteria (like Rhizobium) in their root nodules. These bacteria convert atmospheric nitrogen into a usable form for plants, thereby enhancing soil nitrogen content and fertility.