Hi,
You do not say where you have the image of the tithe map from, but assume you have not actually seen the map at the Record Office, because if you had there is a book “Tithe Award Book” which accompanies the map, by looking at this you would be able to see who owned the land, who occupied each plot and the crop etc., each plot was used for.
From what I read, could be wrong, at the time of the Title 1841
Plot 39b. John Brown Snr., leased this plot from Wyndham, the length of the lease was not for a term of years but for the life of a Mary Prankerds.
Plot 39a, someone named Wheeters, leases this plot from Wyndham, Wheeters apoears to have sub let to John Brown Snr.
So John Brown, does not actually own either plot of land. In any case a Tithe Map/award book would not give any indication of how land was to be left by an owner of such land.
You appear to have only one part of the information I.e. the map, you also need to see the book which goes with the map.
Hope this assists
Spendlove