Grass makes milk, hay doesn’t make much milk, nuts make a bit of milk but not as much as grass. Always get ewes onto grass as soon as you possibly can.
Once you’ve fed a lamb for a few days it’ll gallop several hundred yards to you wherever it is, so you can always top them up in the field after that first few days getting them trained to come to you.
I almost never disagree with shep53 but I do on this one. Whilst yes, a ewe on good grass throughout is at peak production at six weeks, a ewe on poor grass will still produce more milk if moved onto better grass. So I would say, if she’s actually producing milk, her yield will go up if you get her onto grass.
My Jersey cow’s yield varies in both directions according to what grass she’s on. And is currently back up at 11L per day on good grass after dropping to 6.5L when it was mainly hay. I know when it’s time to move her again, it drops to 7.5! She’s running through this time, it’s nearly twelve months since she calved.
Incidentally, we find the pink bales of Meadow Haylage from Livaton Farms does the best job of any forage in making milk. The cows love good hay better, but give us more milk if we give them the haylage once a day.