Tree-cutting began Monday in the Jingu Gaien park district of central Tokyo, a flashpoint for more than a year between environmentalists and real estate interests. Developers led by real-estate company Mitsui Fudosan have a 10-year, multi-billion-dollar plan to build three skyscrapers on the coveted land and to raze a historical baseball stadium, replacing it with a new stadium. A small group of protesters gathered Monday. They object to the destruction of trees in a city that lacks green space and is seeing many parks handed over to commercial interests. The plan is backed by Tokyo Gov. Yuiko Koike, who once was Japan’s environmental minister.