Mae rheolwyr coetir, tirfeddianwyr, y diwydiant coedwigaeth a meithrinfeydd coed yn cael eu hannog i fod ar eu gwyliadwriaeth ac archwilio unrhyw goed derw mawr sydd wedi cael eu plannu'n ddiweddar am OPM, ar ôl i ddau achos o OPM gael eu cadarnhau yng Nghymru ar goed a oedd wedi cael eu mewnforio o Ewrop yn ddiweddar.
Woodland managers, landowners, the forest industry and tree nurseries are being urged to remain vigilant and inspect any recently planted large oak trees for OPM after 2 intercepted findings of OPM were confirmed in Wales on trees recently imported from Europe.