When you say heat treating that covers a broad range of topics. As for working and using dogwood as arrow material and all that entails yes I could answer any questions you might have but let me add a few things that might help you.
You always want to cut dogwood in the winter or after a few good freezes, this allows the sap to go low and you will get a better shaft in the end that wont split out while drying. If you cut dogwood in the summer or spring more than likely as it dries it will get slits and cracks. After you harvest them you can peel them and bundle them in bunches of 6-10 and either tie with cord or use zip ties. These will both loosen after a week of drying and will have to be re tightend.
If you peel the dogwoods when you harvest them they will dry faster then if you leave the bark on them. Cut them longer than desired because the ends tend to split out a little bit.
By bundling the shafts when still wet they will be easier to straighten when dry. Once your shafts are dry you can use a heat gun to straighten them using just your hand and a pair of heavy gloves. For those that are a bit trickier you can build a simple jig out of a 1"x1" x 12" piece of hardwood and drill several holes in it like 3/8" 1/2" etc. you can slide the heated shaft into the hole and use the jig to apply pressure one way or the other.
You can accelerate the drying process if you store the shafts in a hot and dry place.
Maybe this helped you out some....unless you were making a dogwood bow?
E