Can I control or limit the number of lines appearing in a field where I have turned on ""log edits to this field""?

Kathy, yes, you can make a formula field to show just the more recent updates.  That would show in view mode.  I that what you want.

But my better suggestion is to use some formula i can provide which will parse out the most recent value, and who and when it was done.  Then if the user need to see"who done it when" they can edit the record, which will then allow access to the full history of the changes.

Is that what you really want?