The term 'CORN STALK' can be solved by the word 'SILK', which is a four letter word. SILK is a natural protein fiber, some forms of which can be woven into textiles. It is produced by certain insect larvae to form cocoons, and is often used in the production of clothing and other fabrics. Corn stalks are the stems of corn plants, which are tall and woody and can be used for a variety of purposes, such as making paper, fuel, and animal feed.