The Tree Surgeon (1944)

The tree surgeon (a horse) races to the giant sequoia, which isn't feeling well. His techniques, though, seem better suited to treating a person. First, the tree sticks out its tongue (really a squirrel's tail); he takes the temperature, but actually gets his thermometer roasted by a snoring owl. He prepares to inject "vitamin tree-B" but the tree shakes him out; he injects himself by accident and sprouts branches and roots and becomes a nesting place for birds and squirrels. Finally, spotting a syringe of weed killer, with great effort he injects himself. Back to the tree, using suction cups; a termite is busy at work. Using suction brings it out only briefly. The termite gas hose gets snaked back outside, so the horse gasses himself and falls off onto the tree hypo, again. The termite, seeing the commotion, bails and prepares to attack his new host.