Samples can be collected with a soil probe, soil auger, shovel or trowel. The key is to use a clean, rust-free tool to avoid the contamination of the sample with iron. Collect the sample from the soil surface to the depth desired, typically to the plow depth (usually 8 to 12 inches). A clean plastic pail is a good container to place and mix the soil samples in. Avoid using galvanized or brass containers or the sample will be contaminated with zinc. The resultant soil analysis could indicate a sufficiency of these contaminates when a deficiency actually exists.