These Dino's can be knocked out or passive tamed. Keep in mind the kibble or berry cost for knocking it out is much more. Simply stand under its stomach so you don't get hit with their knockback and have the food in your last item slot on your hot bar. Like with most passive taming the time interval between first and second feeding is long but after that it goes as normal. Very simple and easy tames since they do no damage to you when they knock you back. Just be aware of any wild Dino's in the area.

More Diplodocus Taming & KO Tips