Opaque plant covering

1987. The opaque covering-frames are borders of board strengthened by cross or diagonal slips of wood or rods of iron, and covered with canvas, gauze, woollen, or common netting, or oiled paper. They are used for protecting plants from cold, or for sheltering from wind, or shading, either singly, supported by props, or connected so as to form roofs, cases, or enclosures.