Actually they are indications of pure air but also lichen on a tree indicates that the tree may be in declining health. Lichen is a combination of algae and fungus and grows very very slowly. Moss is an indication that there needs to be some better air circulation on that tree. Consider a good pruning in early spring.aving lichens and moss on your tree is an indication that the air around your tree is healthy and clean. They do not harm the tree. They have synergistic relationships with the biosphere of the tree that are more interesting if you leave them there.
Officials said Nevadaâs Lake Mead, the 79-year-old reservoir created by the massive Hoover Dam, registered 1,074.98 feet (327.7 meters) above sea level late on Tuesday, but was able to rise above a critical mark by early on Wednesday morning.
View Photographer's Profile. Hoover Dam on the Colorado River forms the largest reservoir in United States in maximum water capacity, Lake Mead. Previously much of the traffic from Arizona to Las Vegas, Nevada crossed the river on the road across the dam. But since the construction of the Mike OâCallaghan â Pat Tillman Memorial Bridge (Colorado River Bridge), traffic over the dam has been limited. The bridge is 900 feet over the river.