Forestry
In forestry, high grading is a selective type of timber harvesting that removes the highest grade of timber (i.e. the most merchantable stems ) in an area of forest. The stunted, slow growing or poorly formed trees that are left as residuals will, if ecological conditions permit, reseed the space that has been created. Over time the practise of high grading can therefore give rise to forest stands containing stems of less value in terms of timber quality.
The opposite of this practice is low grading, where the lower quality trees are periodically harvested, making the genetic stock faster growing and of better timber quality.
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