So I'm guessing those are different cultivars of Purple leaf plums. Are the leaves alway purple on both trees?
Here's a blurb I found on PL plum cultivars:
"The most common cultivar of the purple leaf plum tree is P. cerasifera 'Atropurpurea,' which grows rapidly up to 30 feet in height. Thundercloud is another common cultivar, growing up to 25 feet tall and wide. The Newport cultivar -- P. cerasifera 'Newportii' -- grows to just 15 feet tall and wide, while the Frankthrees or Mt. St. Helens variety is similar to the Newport cultivar but is faster-growing. Other less-common purple leaf plum tree cultivars include Purple Pony, which grows to about 12 feet tall and Krauter Vesuvius."
I bet both trees will make excellent bows. In my opinion (I know I'm biased) and limited experience (I've only used a dozen or so different woods), there is no better bow wood than purple leaf plum. Works easy, is beautiful, strong in tension and compression, takes heat tempering very well, as well as steam bending, I also find it is fine in my humid environment. And it makes fast, durable bows. That said, I've got a yew recurve in the works that I'm quite fond of, but...
Gabe