Bava Metzia 88: Tithing Produce in the Home, in the Field

If a labourer is permitted to eat while in the field, how should we deal with the obligation to tithe?  The Gemara discusses a number of issues, including:

• Tithing must be done when food is in the home
• That food must have come through a conventional entrance
• Produce brought into the home via the roof is exempt from tithing
• A person is generally permitted to eat without tithing from the food on the vine/trees
• An ox is generally permitted to eat from the food on the ground
• If an ox is muzzled, it should be permitted to eat at the end of its work
• We should not muzzle animals because we should relieve the suffering of any living creature
• If a labourer is muzzled, or forbidden from eating, he should be compensated for that loss
• If a labourer does not eat, the employer is breaking the mitzvah of sustaining one's workers

The rabbis name different vegetables and when each is ready to be processed and then tithed.