139. The residual forest of a block cutting must have the following characteristics:(1) have, inside the limit of the block cutting harvest site, an area at least equivalent to the area of the cutting areas of a block cutting;
(2) have a width of at least 200 m;
(3) be composed of forest stands 7 m or more in height over at least 80% of its area and forest stands of at least 4 m in the remaining area;
(4) be composed of stands having a forest cover density greater than 40% over at least 80% of its area and from 25 to 40% over its remaining area. It may also be composed of stands having a forest cover density of 25 to 40% over more than 20% of its area, provided that that proportion is equal to or less than the proportion of the stands with such a density that are located in forests 7 m or more in height of the block cutting harvest site before the operation;
(5) be composed of forest stands that can produce in commercial species a volume of mature rough merchantable timber of at least 50 m3/ha or, where they cannot produce such a volume, be composed of forest stands equivalent in composition and in area to those harvested;
(6) be composed of forest stands belonging in a proportion of at least 20% to the same type of forest cover as those harvested;
(7) not have been the subject, in the last 10 years of harvesting, of a commercial harvest other than a sylvicultural treatment referred to in the second paragraph of section 142.