Q.Gardening topic
What causes Bottle brush tree to turn brown a few weeks after planting. Was watered 3-5times a week….but when planted the burlap was left on it and it was aprox. 6 inches above the ground. The landscaper brought in fill about 1 month later to cover it

Daily watering for the first 2 weeks is needed. They you can cut back. 3 to 4 inches of hardwood mulch will help with moisture retention but make sure the mulch is back 6 inches from the trunk.
I suspect your tree is not getting enough water.
We do recommend the removal of burlap from the tree roots.
These links have more information.
https://www.gardeningknowhow.com/ornamental/trees/tgen/how-and-when-to-plant-trees.htm
http://www.ehow.com/how_5066352_plant-bottle-brush-trees.html