Sacrificial limbs

The fever tree stands out in a landscape full of interesting trees and shrubs with a very smooth trunk that has a distinct green color. The leaves, way up in the sky, are quite small. Unable to keep up with the energy needs of the tree, the trunk has also been recruited to the task and is full of chlorophyll.  

Mom asked to get out of the safari trunk so she could 'pet' the tree (reminding me of our drive through Death Valley when I was a kid when she talked me into 'petting' a cactus, leaving me with a finger full of spines). I tried to nix this idea -'you'll get eaten by an animal!' Peace was a little more accommodating - 'if an animal eats you, come talk to me.' He stopped by a tree and while mom got her touches in, he was chatting with another driver. Once Mom was safely back in the truck, he asked what she thought of it. 'wait,' he said, 'you touched it?' 
'Well yes!' replied mom.
'You TOUCHED it?'
'Yes!'
'Oh' said Peace. He picked up his radio. 'Peace to the game lodge, hello lodge, come in.' They responded and he said 'yeah, do you have any of the medicine there? For people who touch the fever tree? Yes, one of our guests touched the tree. She signed the waiver, so we're covered. But do we have any of the medicine there? We'll come up right away!'
By the time we were all sharing confused looks and mom was obviously starting to become concerned, Peace turned around with a huge grin - 'kidding!'

The tree received its name from people who slept under the tree at night and awoke covered in yellow pollen. They subsequently developed fevers and in some cases died. It's a bum rap - the malarial mosquitoes who came out at night were the real cause of the fevers.

The land here, specifically the salty soil, isn't great for the trees. Peace pointed out that many of the otherwise healthy looking trees had a brown, dead limb. These crafty trees have developed a mechanism to shunt the extra salt into a single limb, killing it, but sparing the rest of the tree.