White boxes around my 3D model

[Pacizalive]

Hi, I’m quite a newby at Unity and I tried to import a 3D garden model to create a scene.
All the textures are automatically applied to my model but I’ve a graphical issue as you can see on the .PNG.

All the leaves and trees are surrounded by these white meshes or colliders, I don’t know what they are.
Can anybody help me to remove these ? It’s a quite urgent deal thank you
And yes, they remain when I’m in “In-game mode”

[N00MKRAD]

Select one of those leaves to see the material.

Then try each rendering mode (Cutout/Fade/Transparent/Opaque) and see which one works.