THREE RIVERS, Calif.—In the wake of California wildfires, upwards of 10,000 trees weakened by fires, drought, disease or age must be removed, work that will keep a nearby highway closed to visitors who seek the world’s two largest sequoia trees. The hazard trees could potentially fall onto people and cars on the section of State Route 180 known as Generals Highway, or they could create barriers for emergency and fire response, the Sequoia and Kings Canyon national parks said Friday. The highway is closed due to the KNP Complex blaze, which was 60 percent contained after burning 138 square miles (357 square kilometers) of forest, and will remain blocked off to visitors after the fire is out while saw crews cut down trees and trim branches. Cooler weather has helped slow the flames and the area was expected to see rain starting Sunday. The highway connects Giant Forest, home to …