Hemp shiv
The woody core of the hemp stalk, left after the outer fibre is removed.
Hemp shiv is the woody inner core of the stalk, what remains once the long outer bast fibre has been stripped away. For most of hemp's history it was a by-product; today it is the main ingredient of hempcrete.
The material is light, porous and absorbent, which is what gives hempcrete its insulating and moisture-regulating behaviour.
A hemp crop yields both: fibre from the outside of the stalk for textiles, rope and paper, and shiv from the inside for building materials and animal bedding.