The Gemora elaborates on Zevulun's complaint. Zevulun said before Hash-m: You gave to me mountains and hills while You gave to my brothers fields and vineyards. You gave to me lakes and rivers while You gave to my brothers land. Hash-m responded: All your brothers will need to rely on you for the chilazon (a creature that comes up from the water and the blue dye for tzitzis is created from its blood). Zevulun asked Hash-m: Who will notify me if anyone attempts to steal the chilazon from me? Hash-m answered him that the dye produced from a stolen chilazon will be ruined.
It is evident from Zevulun's complaint that fields and vineyards are superior to mountains and hills.
My Rosh Yeshiva, Harav Avrohom Chaim Levin asked on this Gemora from a Rashi in Chumash. The possuk in Parshas Ekev [11:11] states: But the land to which you cross over there to take possession of it is a land of mountains and valleys. Rashi explains that mountains are superior to the plains for on a plain, one can plant in a beis kor a kor's worth of seeds; but on a mountain, one can plant five kors; four on the four slopes and one on the top.
It emerges from this Rashi that it is agriculturally advantageous to have mountains over plains. This is seemingly inconsistent with our Gemora which states that fields are superior to mountains.
I searched but did not find anyone ask this question.
avrohom adler, usa
The implication of the verse in Ekev is that the mountains add value to Eretz Yisrael. That is why Rashi says that mountains can be more valuable for farming than plains.
However, it is obvious that not every mountain is arable - the verse itself distinguishes between mountains that can be plowed and those that cannot (see Yeshaya 7:25, Mishnayos Pe'ah 2:2). Zevulun's contrast between mountains and farmland imply that his mountains were not useable as farmland. (They did, however, grow trees, such as figs, which together with the mountain goat, made the mountains Zavas Chalav u'Devash.
Best regards,
Mordecai Kornfeld
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