By Jordyn Grzelewski From The Detroit News Ford Motor Co.’s U.S. sales plunged by one-third in August compared to the previous year amid an industrywide slide driven by a semiconductor shortage that has dragged on since late last year and pushed new-vehicle inventories to historic lows. Ford sold 124,176 new vehicles in the U.S. last month, down 33.1 percent from August 2020. Truck sales dropped 29.4 percent while SUV sales fell 25.3 percent, according to results the automaker released Thursday. Sales of Ford-branded SUVs were down 24.4 percent year-over-year, with across-the-board decreases for nameplates that were on sale last year. EcoSport was off 64.4 percent. Escape sales were down 32.6 percent. Edge sales fell 39.2 percent. Sales of the Explorer and Expedition, respectively, dropped 56.9  percent and 12.4 percent. The new full-size Bronco SUV had 2,730 sales, down from 3,277 in July, while the smaller Bronco Sport SUV posted 6,698 sales, …