| 摘要 |
PROBLEM TO BE SOLVED: To provide a vegetation sheet and a vegetation bag, in which a mesh size is expanded and movement of vegetation is not suppressed after degradation of yarns of high biodegradation rate while suppressing outflow of a vegetation base material in an initial stage, and growth of plants is promoted, thus an installation site is improved so as to be in the optimum vegetation environment.SOLUTION: A vegetation sheet has mashes 13 formed by weaving or knitting predetermined yarns, and is provided with mesh expansion means for expanding the size of the mesh with lapse of time. The mesh expansion means has twisted yarns 4 each of which is formed by spirally twisting two or more yarns 2, 3 having mutually different biodegradation rates. The mesh 13 is formed by weaving or knitting the twisted yarns 4, and expands by degradation and dissipation of the yarns 2 of fast biodegradation rate. After the degradation of the yarns 2 of fast biodegradation rate, the yarns 3 of slow biodegradation rate are released from a twisted union and become expandable from a spiral state, thus an expansion range of the vegetation sheet is widened. |
