I agree, permission is first and foremost, viability is second.
As you don't have your general location or growing zone listed in your profile, it's difficult to identify this species from the photos provided. However, the landscape, and the sagebrush in the background indicate you are probably in an arid region of the western half of the country. This could be Four-wing Saltbush, but the flowers/seeds don't match, and the leaves are usually a dusty gray-green. Perhaps a Creosote bush?
But species doesn't matter in this case. I don't see a way to get enough roots for this plant to survive anywhere other than where it is now. It's beautiful growing there, and, unfortunately, a dead tree in your yard is not a good trade.
But don't give up. Keep looking. You found this one; there are others that you will be able to collect safely.