TREE FARM LICENCE. TFLs are privately managed Sustained Yield Units. TFLs are designed to enable owners of Crown-granted forestlands and old temporary tenures or the timber licences, which replace them; to combine these with enough unencumbered Crown land to form self-contained sustained yield management units. These licences commit the licensee to manage the entire area under the general supervision of the Forest Service. Cutting from all lands requires Forest Service approval through the issuance of cutting permits. TFLs should not be confused with Certified Tree Farms under the Taxation Act; though some Certified Tree Farm land (Crown-granted) may comprise a part of the TFL. A TFL has a term of 25 years.