What is "Malu'ach"?
Rashi: It is an herb - 'they put Meluchim on gold tables' (Kidushin 66a).
Ibn Ezra: It is moist, like "[Anavim] Lachim."
What is "Si'ach"?
Rashi: It is a tree, like "Achad ha'Sichim." Ibn Ezra - "Lasu'ach ba'Sadeh" is to go between the Sichim (trees).
What is the meaning of "ha'Kotefim Malu'ach Alei Si'ach"?
Rashi: When they were in deserts, they detached 1 from trees and ate Meluchim, i.e. an herb - 'they put Meluchim on gold tables' (Kidushin 66a).
Malbim: Malu'ach is a mixture, like "Memulach Tahor Kodesh."
Ibn Ezra: This is like "v'Katafta Melilos."
What do we learn from "Alei Si'ach v'Shoresh Resamim Lachmam"?
Malbim: Their food was a mixture of tree leaves and roots of Resamim.
