QuestionDoes throwing grass clippings under a pine tree cause any problem for the tree, assuming you are careful to NOT cover the lower branches or get too close to the main trunk?
How about leaves from trees? I sometimes do this to kill unwanted vegetation under my pine trees that I assume take nutrients away from the tree.
AnswerAny mulch should not be thicker than 4 inches--grass is ok the leaves are better. Keep the mulch away from the trunk about 6 inches. The rotting grass will heat up and you do not want this heat near the root collar of the tree (around the trunk at ground level).