This sort of argument could work in discussions with non-hunting friends. "Well, I was afraid some other hunter might come along, shoot the deer, and not cook it properly, so I had to shoot it myself." Or even better: "I am just trying to shoot these deer in case someone buys the land, bulldozes the trees, and puts in a parking lot - then where would they go?" Heh.
Seriously though, I would love to have a good piece of yew, but I do understand not wanting to wantonly cut trees. There are a bunch of big Eastern Red Cedar trees on my parents' farm that I have been eyeing for years, but it makes me a bid sad to cut them since it would change the landscape I remember from my childhood. Still, it doesn't sound like you have THAT many staves...