ASHLAND, Ore. — President Barack Obama has expanded the Cascade-Siskiyou National Monument in southwestern Oregon to protect its rich biodiversity.

The expansion announced Thursday adds about 48,000 acres to a landscape of rich forests, grasslands and shrubs that was established as a monument in 2000. It includes about 5,000 acres in northern California.

Obama said in his proclamation that the expansion will create a landscape that will connect vital habitat, protect the watershed and preserve the area’s extraordinary biodiversity. The monument, originally 65,000 acres, is home to rare plant and animal species.

Conservation groups and Oregon’s Democratic U.S. senators praised the decision.

Oregon Public Broadcasting says detractors have expressed concern that a larger monument would hurt the region’s economy with limits on logging and grazing. The Oregon Cattleman’s Association said in a news release that the decision will have a rippling effect on ranchers, farmers and outdoor enthusiasts.