Which type of tube sampler is best for undisturbed soil samples taken at depths greater than 1 foot, but cannot penetrate stony or rocky soil?

• A. Veihmeyer Tube Sampler
• B. Push Tube Sampler
• C. Split Spoon Tube Sampler
• D. A trier sampler

Answer: (A)

Undisturbed sampling aims to preserve the soil’s natural structure as you extract a core. A Veihmeyer tube sampler is a short, rigid, closed-ended cylinder that is driven into the soil to capture a relatively undisturbed cylindrical core. It works well for soils that are soft to moderately firm and allows sampling to depths beyond a foot without excessive disturbance of the soil fabric. Because it relies on penetration into acceptable soils rather than forcing through hard material, it is best suited to contexts where the soil can be penetrated but is not stony or rocky. In soils that are too rocky, penetration becomes impractical, so a method like the Veihmeyer tube remains the most appropriate option among the given choices for obtaining an undisturbed sample at depths greater than 1 foot when the soil isn’t too hard.