Reference for Pesachim 105:10

סימן לנחלים קנים נפקא מינה לנחל איתן סימן לשפלה שקמה נפקא מינה למקח וממכר השתא דאתית להכי כולהו נמי למקח וממכר:

nor of the palm trees in the highlands nor of the fruits in the valleys.<span class="x" onmousemove="('comment',' Because these are of inferior quality. The same idea is expressed by R. Simeon b. Gamaliel when he says that palm trees are an indication of valleys, i.e., the best grow in the valleys. His other statements bear a similar meaning.');">²⁵</span> 'An indication of streams is reeds.' The practical difference is in respect of the rough valley' [nahal ethan].<span class="x" onmousemove="('comment',' V. Deut. XXI,4 . Nahal is a stream which in summer dries up and leaves a valley bed. The presence of reeds along the margin of the valley indicates that this is a fitting place for the purpose.');">²⁶</span> 'An indication of lowlands is the sycamore tree.'

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