The next subject is the idea of HEFKER (ownerless) that one must not guard the fruits that grow during Shmitta. A Jew with fruits growing on his land must open the gates and allow others to enter and pick fruit as they wish. The Gemorrah is found in tractate Yevomos page 122a: The fruits have been guarded. Rashi: It was the seventh year. Our Gemorrah brings a Braisah that teaches us about a non-Jew selling produce. The words he uses each have two possible meanings and our Rabbis hold that we should be lenient considering that normal salesmen only speak about the high quality of their produce and would never dream of saying that their produce had problems of Kashrus. When the salesman said the fruits were guarded he means that they were well taken care of and nothing left for chance. The other meaning would have been that they were guarded during the seventh (Shmitta) year and that the Torah had been violated. Please refer to VaYikra chapter 25 verse 5 and commentaries where the Torah commands us not to keep 7th year produce for ourselves, but rather to open the gate and allow people to take for free (HEFKER). Rashi's opinion all over Shas is that closing the gate on 7th year produce does not cause any prohibition or Kashrut problem with the produce. One should note that our Gemorrah is difficult to explain using Rashi's opinion since there is no prohibition on eating this produce, unlike Orla (3rd year produce) and Netta Revai (4th year produce) which are mentioned in the same sentence and are certainly prohibited. Rashi just commented his regular opinion on this subject, asked the question how this can be true, and gave no further explanation. This is rare indeed! Those interested can find what the Ramban suggested as answers to Rashi's question in the Ramban's commentary to the Chumash VaYikra chapter 25 verse 5 (look for it in the second half of the long discussion there.) The opinion of Tosefos in many places is that as soon as the Jewish farmer closes the gate on 7th year produce, it becomes forbidden exactly like Orla and Netta Revai. This prohibition is called SHAMUR (guarded). A similar case to SHAMUR is NE'EVAD which is a field that was tended during the Shmitta year. The example is a vineyard pruned during Shmitta, resulting in the production of grapes. Those grapes are called NE'EVAD. Both SHAMUR and NE'EVAD are reasons NOT to eat fruits and vegetables grown by Jews during Shmitta in the land of Israel. There are some Rabbinical authorities who are lenient like Rashi in rare cases where there are no alternative fruits and a person is ill and should eat something.