I've gotten my oils from Young Living also. These oils are the gold standard.
When I collect swarms, I always use a drop or two of lemongrass oil from this supplier on a cotton ball and dab some on the inside of the box I put the swarm into. The bees love it. After collecting a very large swarm , I got a call the next morning from the gal who originally contacted me. She said there were "thousands" of bees on the sidewalk in front of the tree I removed the swarm from. This got me curious. I rode over and sure enough, there weren't thousands but there were a good many bees on the sidewalk. A few hundred stragglers from the night before. They were gathering around the sodden cotton ball I dropped in the dark while it was raining. I scooped them up along with the cotton ball. I guess they'd have done the same with any brand lemon grass oil, but it was an interesting sight to see.