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The term high grading in forestry, fishing and mining relates to selectively harvesting goods, to “cut the best and leave the rest”. In mining, it can also be a term for theft.
[edit] ForestryIn 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. [edit] FishingHigh grading is a practice of selectively harvesting fish so that only the best quality fish are brought ashore. The practice is popular in situations under individual fishing quotas where only a limited number of fish are allowed to be harvested. Following the letter, but not the spirit of the law, fish are caught, and if not considered optimal, thrown back into the ocean. The practice of high grading allows fishers to get high prices for their limited catch but is environmentally destructive because many of the fish returned to the water die. [edit] MiningIn mining, high grading refers to mining out the portions of the orebody that has the highest grade of material to be mined, however it may also refer to the concealment and theft of valuable gold or silver ore by miners for personal profit. Common in the United States in the late 1800s and early 1900s, high graders would usually conceal gold ore in a pocket or lunch pail, or internally within the body, and later attempt to fence it on the black market. As mining companies became more aware of the growing problem, they built changing stations where they forced the miners to shower after their shift in the mines, making it easier to foil attempts at theft.
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