A great little guide to go by I found at Yahoo.com golf section:
Chip or Putt? - Dr. Jim Suttie
- You have more than half the green to work with
- The green is slow or plays uphill
- your ball is sitting down
- The fringe is wet or bumpy
- You're more than four paces off the green.
- The hole is cut close to the edge
- The green is fast or slopes away
- your ball is sitting well
- The fringe is dry and smooth
- You're fewer than four paces off the green.