proper schema design input

I'm designing a simple fmp9 db for a farming project and would like input on its schema. The farm has 3 plots. They keep 3 input logs and 1 output log, and they keep track of weekly user hours per plot, with NO concern for which log the hours applied. no data needs to be summated across plots.

At first I thought I'd have the following tables...plots, logs, users. But it turns out the 4 fields in all the logs are exactly the same (date, veggietype, variety, amt), so I wonder if the logs db is not necessary, and 'log type' should just be a field in the plot table. nothing will be summated across logs. I've considered having separate tables for input and output, and I am trying to think of why fmp would handle this better than excel.