The picture you show as the new tree, with the white mulch; does not have all that amount of sticks and that huge pole and cross boards around the small tree. So I supposed you made all of that after... I think, that doing the digging for the pole, disturbed the root of the plant, and besides all those sticks are just asfphyxiting the plant. So, regardless watering, warm and cold etc... the plant have been afflictedby its surroundings...
