Er bod gwaith ymchwil yn dangos bod Chalara yn gallu cael ei gario hefyd yng ngwynnin a rhuddin y pren (y sapwood a’r heartwood), nid yw wedi’i brofi eu bod yn gallu achosi heintiadau newydd.  Nid ydym felly ar hyn o bryd yn argymell cynllun eang i dorri coed aeddfed na chyfyngu ar symud pren ynn.
Although research has demonstrated that Chalara can be transported in the sapwood and heartwood of ash it is not established that new infections can then arise from this material and we are therefore not currently recommending the large scale felling of mature trees nor restrictions on the transport of ash timber.