I am new to both of these plants. I have several Brug cuttings that I hope to get to grow this summer and
Karma-H-T has already sent me some helpful tips.
I have just posted a picture in the Identification forum of two Datura plants I purchased. If you could take a look maybe someone can tell me just exactly (or a good guess) what I got.
Tree Climber, many interspecies hybrids exist with the Datura so identifying which one you have is not that easy. On top of that, flower, leaf, and seed pod are always good indicators of possible genetics if one is into hybridizing or just finding out what species, subspecies, or hybrid they have. I took a look at the picture you posted and to the best of my knowledge the one on the left may or may not be a Datura wrightii, but please bear in mind I detest Datura so I may be wrong. I love Brugmansia on the other hand. Are you thinking of hybridizing Datura? If so, D.ferox is hybridizable with quercifolia, stramoniumm , leichhardtii and D. discolor to my knowledge. Of course, D.leichhardtii looks to be a good bridge plant for species of Datura that won't normally hybridize with each other. As leichhardtii is hybridizable with 6 of the 9 different species of Datura if memory serves me.
Hope that helps,