This was an experience. A small branch fell out of my pecan tree. I was on the way to toss it in the back yard "pile", but as I passed my egg - I thought why waste the flavor? That evening after lighting the egg, I folded the branch and tossed it in, leaves and all. The leaves went up in a flash. I closed the lid and went in to get the burgers.
Two min. later with the burgers in hand, I opened the lid. This is when the excitement began... There was an explosion similar to an M80, I now find myself in the middle of flying red streaks of fire. One lands IN MY GLOVE... One puts a hole in my shirt. After ripping off the glove and brushing embers off my new table with it... What was that? Will it happen again? CLOSE THE GRILL! As I lower the top I get explosion #2. This time, all I get is some minor red stuff out the top of the egg and some interesting dust out the bottom. Interesting how quickly your heart rate can get to 150.
In about another 10 seconds I realize that maybe I loaded some raw pecans in the fire... that was smart. I closed both the top and bottom vents. Two more muffled explosions and 5 min later, I figure its safe to toss the meat on the grill... Great pecan flavor.
I now have one less shirt, some much more substantial grilling gloves, and I only use "chunks" of pecan.