Seaweeds
"A general term for the plants comprehended in the order Algae of the Linnaean class Cryptogamia, known as flowerless plants. It includes not only plants growing in the sea, as the name Seaweed implies, but also in fresh water, and on moist earth, rocks, stone, and living and diseased vegetable substances, in the form of slime and jellies" (Smith). Seaweeds are very largely used as manure in many districts around the British coasts, and in the Channel Islands, and are much esteemed for this purpose, owing to their richness in the foods required by plants, and to their rapid decay after being dug or ploughed into the ground. They are regarded as peculiarly useful in promoting the growth of Potatoes, and also as beneficial to Turnips; in fact, they especially assist the growth of plants that contain a good deal of water in their tissues when mature. Besides the Seaweeds themselves, the masses of them employed as manure have usually mixed up among them a good deal of decaying animal matter, from dead sea-animals on or in the plants, and this adds considerably to their value. They are very rich in Potash and Soda compounds, but rather poor in Phosphates; hence, it is well to mix with them some bone-dust, or other manure rich in Phosphates, before spreading them on the soil. See also Manures.