Mishnayos Peah Perek 3 Mishnah 1

מלבנות – a square garden-bed, and because they were made like the white frames, they are called garden-beds/plots.

שבין הזיתים – and the same law applies for all other kinds of trees, and he (i.e., the anonymous Tanna/teacher of the Mishnah) took [the word] “olives,” to teach us, that even olives are liable in Peah/the corner of the field [to be left for the poor], are not from the legal decisions of the School of Hillel, and all the more so, the rest of the trees which are not liable for Peah/the corner of the field, for it is obvious that they did not make this legal decision.

ב"ש אומרים פאה מכל אחד ואחד – from each small garden-bed/plot and garden-bed/plot, since the small garden-beds/plots stand each piece detached and they do combine with one another, as the School of Shammai holds that the olives are detached. But where the beginnings of the rows are combined with each other, they admit that they are not separate. And at the time when the trees are distant from each other until in the ground, there is a field requiring one Se’ah of seed (a square measure), fifty cubits by fifty cubits and there aren’t ten trees in it, the School of Hillel admits that we give Peah for each and every garden-bed, since the trees are far apart, things appear that it is not for the trees that these small garden-beds were made. And when the trees are joined closely and there are ten trees in less than a field requiring one Se’ah of seed, the School of Shammai admits that we give one Peah for everything, they only disputed when there are ten trees in a field requiring one Se’ah of seed.