What is the Chidush that it prepares its food?
Rashi: It prepares for itself; it does not steal from its colleague.
Why does it mention "Kayitz" and "Katzir"?
Malbim: Katzir is before Kayitz. All the days of Katzir, it gathers seeds of grain for it to eat. Afterwards, when Katzir is finished, Kayitz begins, and there are not grain seeds in the field. It strives to prepare its food, to put it in a guarded place, and to cut the ends of the seeds, lest they sprout. Take Musar from this, to gather the laws of Chachmah and Divrei Torah in your heart all the days of your youth. Do not say '[I have] enough'! After you gathered all of them, understand them with your Sechel - first one should learn [the text of teachings], and afterwards understand them (Shabbos 63a). Prepare for yourself provisions for the designated day, just like the ant prepares all the days of winter. Only one who toiled on Erev Shabbos will eat on Shabbos (Avodah Zarah 3a)! Similarly, after you gathered the laws of Chachmah, prepare them with your Binah and Sechel, so they will be food of the Nefesh. Chachmah and Torah are food of brightness of the Nefesh for the designated day [after death].
