How did Mongol armies in the time of Genghis Khan "live off the land"?

by Juub1990

The Mongols at the time were famed for the speed at which they moved. I read it's because unlike the other armies at the time, they didn't have to worry about supply trains coming from their cities slowing them down. They simply rode their horses and lived off the land.

My question is the following; how did the Mongols live off the land? From my understanding, they weren't farmers (and how could an army farm while moving anyway?), and the steppe was mostly grassland and pasture, hardly crops intended for human consumption. Then I thought they perhaps carried cattle and sheep with them, but wouldn't that slow them down considerably?

So how did those armies famed for their speed travel such enormous distances and kept fed and hydrated?

Thank you

Yeangster

This is about a different era and army, but I asked this question about 'living off the land' in Napoleonic warfare and /u/dandan_noodles gave an excellent answer here

But in short, 'living off the land' in warfare did not mean in a survivalist or Bear Grylls sense. It basically meant confiscating food from people who were living there. Now the Mongols did do things that Napoleonic armies didn't, but I'll let someone else with more expertise go into the details.