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In agriculture and gardening, row cover is any transparent or semi-transparent, flexible material, like fabric or plastic sheeting, used as a protective covering to shield plants, usually vegetables, primarily from the undesirable effects of cold and wind, and also from insect damage.〔 Article marked reviewed by publisher in 2012.〕 ==Material== Commercially available row cover is usually a lightweight synthetic, such as clear plastic (polyethylene) or spunbonded polyester. It is placed directly above rows of crops on a supporting framework—often, on wire hoops to form a low tunnel—and usually left in place for several weeks until crops are well-established.〔 Floating row cover is extremely lightweight row cover fabric that can be placed directly over plants, without need for a supporting framework, instead being simply anchored to the ground against wind.〔 Another form of light weight row cover is made from High Density Polyethylene (HDPE) and is a knitted fabric. It is strong and the manufacturer claims a life of 8 years. It is designed with a low shading effect (16%) and allows natural air flow and rain and water penetration. It also protects from light frosts, strong winds and hail. It is used on low tunnels. It comes in a variety of widths and lengths. A protective tunnel formed with row cover is sometimes called a ''cloche'',〔There is some usage of the term ''cloche'' to include row cover tunnels, or other season extension covering (as in this somewhat ambiguous (Rodale gardening encyclopedia definition ))〕 although a cloche, or bell jar, commonly refers to a distinct type of protective covering, made of glass or plastic, usually placed over individual plants. No longer in general use, a type of cloche employed in Europe involved panes of glass attached with wire to form continuous tunnels to protect rows of crops. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Row cover」の詳細全文を読む スポンサード リンク
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