Allow wet soil to air dry before placing in boxes. Write the sample ID in permanent black ink. Close box flaps securely to prevent spillage during shipment.
Loose flaps allow soil to spill from the box and become mixed with other samples.
Place individual sample boxes upright in a sturdy cardboard container for shipping. Used farm chemical boxes are suitable. Pack individual sample boxes firmly in the shipping container. Fill empty space in the shipping container with crumpled newspaper or equivalent packing material. Stack samples no more than three boxes high.