Hello, I check the tortoises table for your reference.
Common name : Kale (Curly Kale, Collard Greens, Spring Greens)
Latin name : Brassica oleracea (Acephala Group)
Family name : Brassicaceae
kale has a high calcium content and only half the oxalates of dandelions, making it a potentially nutritious food. Unfortunately, like all the brassicas, it is also high in oxalates (which interfere with the uptake of calcium) and goitrogens (which interfere with iodine uptake, resulting in thyroid problems). However, kale also has a high iodine content, which lessens the goitrogen effect and it is therefore acceptable to feed to your tortoise in moderation, especially in winter with non-hibernating tortoises, when fresh weeds are scarce.