Any problems with this backyard practice strategy?

[aeijtzsche]

Recently I've been wanting to practice more than my wallet can take care of as far as range work, so I got a bunch of those yellow "Almost Golf" practice balls, that seem to be endorsed by Pelz. Supposedly they fly 33% of an actual golf ball. I don't have a lot of room, so what I do is set up 25 yards from a fairly large tree, and aim to hit the tree dead on. I use a Pitching Wedge, take half swings or so, and try to hit the tree about 20-30 feet up the trunk of this tree.

My question is twofold:

One, does this seem like a worthwhile thing to do...which relates to the second part,

Is there room for errors to creep in that would be harder to spot because of the curtailed ball flight and will those practice ball mask or exaggerate certain ballstriking issues?

I figure 25 yards is enough to see if there is significant spin on it, and I figure if I can hit the tree every time I must be doing something right. My worry is that there is some factor I'm not thinking of that could be detrimental to practice this way.

 

[swingobsessed]

I hit those from time to time. 25 yards isn't enough to see if anything happens at the end of the ball flight. They can hook or slice just like a real ball right at the last moment. Also, they go way furthur than 33% of the distance of a real golf ball...at least in my experience.

 

[Jared Willerson]

If they go 33%, then I should be able to hit a normal 7 iron around 230 - 240, but alas, I do not. According to the yardage I hit those almost golf balls. I find them to be around 40-42% of a normal ball.

I practice with them all the time. I love them, you can hit them anywhere and they won't break anything. (Helpful Hint: don't hit them in the house, your wife WILL NOT understand)