Choreish / Plowing I

 Melacha / Activity:  Choreish / Plowing

The Mishna is Massechet Shabbat states:

מַתְנִי׳ אֲבוֹת מְלָאכוֹת אַרְבָּעִים חָסֵר אַחַת: הַזּוֹרֵעַ, וְהַחוֹרֵשׁ...

MISHNA: This fundamental mishna enumerates those who perform the primary categories of labor prohibited on Shabbat, which number forty-less-one. They are grouped in accordance with their function: One who sows, and one who plows…

Definition: Any activity that improves (softens) or beautifies the condition of the ground in preparation for planting. This includes plowing, digging, making a furrow in the ground and smoothing out the soil. Also included in the melacha is removing rocks or thorns from a field and fertilizing in a field. 

Choreish in the Mishkan: The first eleven shabbat activities were needed in the Mishkan in order to produce dyes to color the tapestries in the Mishkan. The dyes were derived from plants and herbs that were grown for this purpose. 

According to others the first eleven activities were needed to produce the Lechem Hapanim (Showbread) and other meal offerings brought in the Mishkan.

There is no minimum size of land required to violate Choreish since even a very small hole can be used to plant a seed. Also, no tools are required for the action to be considered Choreish.

What kind of soil does Choreish Apply to?

Choreish does not apply to fine dry sand as any action done to the sand does not affect change. Also the sand will fall back into the hole.

Choreish does not apply where plowing could not possibly improve the land for planting purposes. If the land is not arable, the prohibition does not apply (example - dessert soil).