What a golf ball can do...

I regularly hit golf balls in my back yard, into a practice net designed to contain them ... or so it's supposed to. A few months ago I was hitting with my driver and I wacked one and then heard the trees in the back by the fence making noise like a golf ball was flying through them ... I never saw that ball again, nor did I hear it land. I repaired the hole in the net, but it happened again a week later and I decided that I could no longer hit my driver into the net ..  having a golf ball leave the yard like that is tooo scary!

Forward to today: I have the practice net in front of the wooden fence to serve as a stop for any balls that go through the net. I have sense made several repairs to the net. The dent left by a golf ball hit from a 3 iron leaves dimples on the fence that you can feel. Today, I found out a ball hit by my driver will do to the fence after it goes through the net ... break it. (My swing speed said the driver was swung at 115 mph, which is my normal driver speed.) So, I'm now thinking that the fence is not a good back stop and will hit shorter irons until I figure out another solution to keep balls in the back yard. I also have "Birdy Balls", which I've broken, but not the professional line of them. And I'll hit foam balls too. They're fun to hit, but can go over the fence's too; but they're not breaking anything.