NEW YORK (AP) ¿ Shares of U.S. Energy Corp. climbed in Tuesday premarket trading after the diversified natural resource company said a well in the Williston Basin in North Dakota began initial production. Shares of the company rose 21 cents, or 4.2 percent, to $5.25 in trading before the opening bell. U.S. Energy on Monday said the well, which is operated by Brigham Exploration Co., produced about 2,769 barrels of oil and 3.75 million cubic feet of natural gas per day, or 3,394 barrels of oil equivalent per day, during a 24 hour period. U.S. Energy's has a 65 percent interest in the well. The company said oil sales from the well have begun, and natural gas sales will start when the gathering system is connected, which is estimated to take up to 120 days. Jefferies & Co. analyst Subash Chandra said the well achieved the highest flow rate in Brigham's Rough Rider region.