What characteristic indicates clay loam soil?

The indication that clay loam soil forms a weak ribbon is significant because it reflects the balance of soil components that characterizes its texture. In soil texture, a weak ribbon means that the soil can hold together momentarily when compressed, indicating sufficient clay content while still retaining properties of loam.

Clay loam is a combination of clay, silt, and sand, and the clay component lends to the soil's ability to form a short, cohesive ribbon when pressed between fingers. This weak ribbon suggests that while the soil has clay's adhesive qualities, it is not overly plastic or sticky, which would involve a higher clay content that is typically more characteristic of heavier clay soils.

The formation of such a weak ribbon helps in identifying clay loam during soil evaluations, as it visually and texturally conveys the mixed properties of different soil particles, enabling its classification.