Kilayim, Chapter Two, Mishnah Ten
The first part of our mishnah is a continuation of yesterdays mishnah. Yesterday we learned that if a person wishes to sow his field with different species he must leave an empty plot in between the sown plots. The empty plot must be the size of a bet rova (1/24 the size of a bet seah). In our mishnah we learn that any plot which cant be used for sowing seed serves as a break between the different species, even if the plot is not completely empty.
The second half of our mishnah teaches how far one must separate different species in order that they shouldnt look like kilayim.
1) Whatever there is within a bet rova [which separates different species] is included in the area of a bet rova: the space which vine roots consume, a grave, a rock, [all] count in the measure of a bet rova.
2) [One who wants to sow one type of] grain [in a field of another type] of grainthe measure is a bet rova.
3) Vegetables within [a field of other] vegetablesthe measure is six handbreadths.
4) Vegetables within [a field of] grain, or grain within [a field of] vegetablesthe measure is a bet rova.
a) Rabbi Eliezer says: vegetables in [a field of] grainthe measure is six handbreadths.
Section one: If there is something within the bet rova plot that prevents one from sowing there, the bet rova still counts as an empty plot serving to separate the two different species. The first object is the space around a vine that the vines roots take up. Thus if there is a plot planted with a vine, the vines roots, which are halakhically considered to take up six handbreadths (we will return to this subject in 3:7), and these six handbreadths count toward the empty bet rova. So too a grave and a rock all count towards the empty space needed to separate between the different species, even though it is obviously impossible to plant on a grave or on a rock.
Section two: One who wants to plant one type of grain in a field of another type of grain must distance the two one bet rova from each other. According to the Rambam this must be a squaremeaning 10 1/5 cubits by 10 1/5 cubits.
Section three: Vegetables are planted in smaller plots, hence one can plant them closer to each other (imagine the tomato or cucumber garden my Dad has behind his housetheyre very good, so if youre ever in Margate, NJ in the summer..). The distance is only six handbreadths square, far smaller than that for grain.
Section four: The mishnah now deals with cases where a person wants to put grain in a field of vegetables, or vice versa. According to the first opinion, the two species must be kept at a distance of a bet rova, since one is grain. According to Rabbi Eliezer, he must distance them only six handbreadths, the measure for distancing vegetables.