Mae cyfyngiadau llymach ar fewnforio coed derw wedi cael eu cyflwyno heddiw i amddiffyn coed brodorol rhag y pla coed Gwyfyn Ymdeithiwr y Derw (OPM).
Tighter restrictions on the import of oak trees have today been introduced to protect native trees from the threat of the tree pest oak processionary moth (OPM).