The toothache tree (Zanthoxylum clava-herculis) is a tree you will want to know about due to its great medical uses. Chewing on its leaves or bark causes a numbness of the mouth, teeth, and tongue/ This is great if you have an issue inside your mouth that needs to be taken care of, and of course this is where it gets it name.
The tree was used for these medical purposes by Native Americans. Unfortunately for many people this great tree is not real common anywhere, and is confined to parts of the Southeastern USA. However, if you reside in an area where this tree is found you will certainly want/need to know how to recognize it.
The good news is that even though the tree is not common you aren't likely to simply walk by it without noticing it. This is because the bark of the tree is very unusual. The bark of the tree has what looks like pyramids all over it. Not thin spines like a rose bush or large stickers like devils walking-stick but honest to goodness bumps that look exactly like 1/2 inch tall pyramids. You absolutely can not over look it even if you tried. The leaves are compound, alternate and each leaflet is lance shaped.
The scientific name is Zanthoxylum clava-herculis if you want to look up more about it. Above is a picture of the bark... which is all you really need for identification.
If you want to grow one probably the best method would be to cut and plant sections of root about one or two inches long. Plant horizontally in good organic rich potting soil. Moisten and mulch until growth begins. Cutting should be taken in the winter and the plant should start grow well in the spring.