There are certain data sections in the field inventory that you are able to edit. 

To begin editing the data - hit the edit icon found on the main  inventory page. 

Once you click edit, the actual inventory will expand to allow you to begin the editing process: 

You are able to edit: 

• Planned planting date 
• Completed planting date
• Planned harvest date 
• Completed harvest date 
• Estimated tonnage
• Actual tonnage 
• Switch a plot from active to closed 

Once all necessary changes have been made, simply click 'Exit edit mode' at the bottom right hand corner of the screen and return to the main page, with the changes saved.