Rushes is thatch. I don't know if any thatch will work but the node line number of 3, 4, and 5 should have them, at least that's where I've found them. As for bola taming, be mindful with it.
Passive Taming:
Simply feed the animal the desired food, so far on my island I've tamed Sheep, Chickens, and Cows
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Sheep: Camomile
Chickens: Berries
Cows/Bulls: Rushes
Horses: Sugarcane
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When you are bola taming an animal, you do have to get it to low health and throw the bola at it, but be very careful as it can still attack with it's head. Make sure you either have a pen set up with the animal in it all ready, or you build one around it, because it likely will take multiple bolas to tame something. I don't know how that would affect the effectiveness of the tame cause you'd have to damage it again, I also don't know if the bola can be refreshed before it runs out by throwing another.
