Why do most ecologists and foresters consider tree plantations to be more like cropland than forestland?

Most ecologists and foresters consider tree plantations to be more like cropland than forestland because foresters are casual and spontaneous plantations, while cropland is organized and planned, and usually, it develops only certain types of plantations, while forestland is structured as an ecosystem where plants can grow in a spontaneous way. 

Answer decreased soil salinity;

Answer they are produced by collision of tectonic plates;