Straw has been used as a building material in England for maybe a thousand years. It used to be mainly used in roofing - thatching was a trade for a very long time, and you still see thatched houses in the countryside. Obviously it needs maintenance, and occasionally you'll hear of a thatcher finding something ancient hidden away for centuries in the thatch.

Can't say I understand how it works, but it's a very effective means of building.