Looking at the types of horticulture practice that we may want to present in the Horticulture best practices in the Propagation sub-section, we plan to have seed, cuttings, propagating from division and we could have grafting or layering. Is the latter used for rare plants? Can you please share your examples?
I haven’t used air layering for rare species, but I developed air layering techniques for several cultivated species back in the day when I was the propagator at a wholesale nursery. I definitely think it could be used for conservation of many of our woody species as well. Your Purshia would be a good candidate.