can't resize terrain?

I created a blank terrain, and neither the gizmo nor the inspector will change it's size. the size shows that it's been changed in the inspector under scale though. i've tried center and pivot. could the other terrain in the scene be doing it?

Go to Terrain > Set Resolution in the menu, that'll let you set the size

Can you do that by code (out of a script) too?

http://forum.unity3d.com/threads/set-terrain-size-via-script.159180

In Unity 4.6 you do not use scale. You go to where the icons are for setting skins (textures), its under the gear icon. Its at the end of that row where you choose trees, or plants, etc. You set the size under Width and Length. It’s default is 2000 x 2000.

You do not need to mess with scripting it, that will just mess things up.

Hope this helps.