Terrain has very high draw call

Hi, our artists have created terrain 150x150 at 513 heightmap resolution inside the Unity editor. The draw calls can easily reach 100 draw calls when I zoom in the camera (the number is varied depending on the area of terrain). The scene has only one terrain. Is this normal? I intend to release the game to iPad2. I doubt that the hardware can run it. I’ve read that terrain is finally supported on iOS and Android. But at this rate, is it actually usable on such platform? Or what can be done here to reduce the draw calls? Is it better to model the terrain in other program and import it as a mesh into Unity?

Terrain are not usable on iOS: too slow.

As a workaround, you can export the raw data of your Unity-authored terrain, open it in your favorite 3D-modeling tools and export a low-poly version to be used on iOS.