I hit the ball with a club but the ball goes no where near the tree
I dont understand fully what you mean by this but following on from what you say then I dont think this has anything to do with Blitz collisions.
First of all you would have to set up the collisions using EntityType and EntityRadius(for spherical) and then enable collisions between different entity types with the Collisions command.
The collisions are calculated in real-time whenever the UpdateWorld is processed and are never precalculated.
Check that you are using the correct collison type and that your radii or bounding boxes are the correct size. If you have scaled your entities then this also scales the radius or size of the bounding box.