 As the 1830s drew to a close , the fur industry slowly began to die as silk replaced beaver fur as a desirable clothing item . By this time , also , the beaver population of streams in the Rocky Mountains had been decimated by intense hunting . Furthermore , frequent Native American attacks on trading posts made it dangerous for employees of the fur companies . In some regions , the industry continued well into the 1840s , but in others such as the Platte River valley , declines of the beaver population contributed to an earlier demise . The fur trade finally disappeared in the Great Plains around 1850 , with the primary center of industry shifting to the Mississippi Valley and central Canada . Despite the demise of the once @-@ prosperous trade , however , its legacy led to the opening of the American West and a flood of settlers , farmers , ranchers , adventurers , hopefuls , financially bereft , and entrepreneurs took their place . 
 As the 1830s drew to a close , the fur industry slowly began to die as silk replaced beaver fur as a desirable clothing item . By this time , also , the beaver population of streams in the Rocky Mountains <a href='been_done' title='1'><mark>had</mark></a> been decimated by intense hunting . Furthermore , frequent Native American attacks on trading posts made it dangerous for employees of the fur companies . In some regions , the industry continued well into the 1840s , but in others such as the Platte River valley , declines of the beaver population contributed to an earlier demise . The fur trade finally disappeared in the Great Plains around 1850 , with the primary center of industry shifting to the Mississippi Valley and central Canada . Despite the demise of the once @-@ prosperous trade , however , its legacy led to the opening of the American West and a flood of settlers , farmers , ranchers , adventurers , hopefuls , financially bereft , and entrepreneurs took their place . 
As the 1830s drew to a close , the fur industry slowly began to die as silk replaced beaver fur as a desirable clothing item . By this time , also , da beaver population of streams in the Rocky Mountains done been decimated by intense huntin . Furthermore , frequent Native American attacks on trading posts made it dangerous for employees of the fur companies . In some regions , tdaindustry continued well into thda840s , but in others such as the Platte River valley , declines of thedaaver population contributed to an earlier demise . The fur trade finally disappeared in the Great Plains around 1850 , wid the damary center of industry shifting to the Mdaissippi Valley and central Canada . Despite the dedae of the oncda-@ prosperous trade , however , its legacy led to the opening of the American West and a flood of settlers , farmers , ranchers , adventurers , hopefuls , financially bereft , and entrepreneurs took their place .