<P> Nelson chose the date in order to maximize participation on college campuses for what he conceived as an "environmental teach - in". He determined the week of April 19--25 was the best bet as it did not fall during exams or spring breaks . Moreover, it did not conflict with religious holidays such as Easter or Passover, and was late enough in spring to have decent weather . More students were likely to be in class, and there would be less competition with other mid-week events--so he chose Wednesday, April 22 . The day also fell after the anniversary of the birth of noted conservationist John Muir . The National Park Service, John Muir National Historic Site, has a celebration every year on or around Earth Day (April 21, 22 or 23), called Birthday - Earth Day, in recognition of Earth Day and John Muir's contribution to the collective consciousness of environmentalism and conservation . </P> <P> Unbeknownst to Nelson, April 22, 1970, was coincidentally the 100th anniversary of the birth of Vladimir Lenin, when translated to the Gregorian calendar (which the Soviets adopted in 1918). Time reported that some suspected the date was not a coincidence, but a clue that the event was "a Communist trick", and quoted a member of the Daughters of the American Revolution as saying, "subversive elements plan to make American children live in an environment that is good for them ." J. Edgar Hoover, director of the U.S. Federal Bureau of Investigation, may have found the Lenin connection intriguing; it was alleged the FBI conducted surveillance at the 1970 demonstrations . The idea that the date was chosen to celebrate Lenin's centenary still persists in some quarters, an idea borne out by the similarity with the subbotnik instituted by Lenin in 1920 as days on which people would have to do community service, which typically consisted in removing rubbish from public property and collecting recyclable material . Subbotniks were also imposed on other countries within the compass of Soviet power, including Eastern Europe, and at the height of its power the Soviet Union established a nationwide subbotnik to be celebrated on Lenin's birthday, April 22, which had been proclaimed a national holiday celebrating communism by Nikita Khrushchev in 1955 . </P> <P> There are many songs that are performed on Earth Day, that generally fall into two categories . Popular songs by contemporary artists not specific to Earth Day that are under copyright or new lyrics adapted to children's songs . </P>

Who was selected as earth days national coordinator