Steedgrass is the rarest thing one can find while gathering herbs with a drop rate of .6%. Often steedgrass will sell for 500-1000 gold per herb. This is due to its use in taming, a skill that is used to create a mount.
Creating a MountEdit
First find some steedgrass. Then buy the skill Taming along with a taming whistle. The skill can be found at an arcanists place and the whistle can be bought from the merchant. Then create a mount figurine, which will appear within a backpack. The kind of mount that is created depnds on the race of the creator. This is talked about more within Racial Mounts.
Summoning a MountEdit
Aim at the ground ahead of where the mount should appear. Double-click the mount figurine within the backpack and it will appear in full size on the ground.
Note: Anyone can run up and steal a mount unless it is being ridden. Be sure to spawn it away from other players, and don't leave it unattended.
De-spawning a MountEdit
Walk up to it, while aiming at it, and press alternate use (default G) to make it into a figurine again. The figurine will appear in your backpack.