I spent hours today trying to create a plant that used several curved planes with alphas aplied.  This creaeed the alpha sorting glitch.  After a lot of trial and error, I have something that mostly works.   I am trying to create a mesh plant.  Using a curved plane, I duplicate it and flip the normals so it has the same mesh for the top and bottom.  I do not join the meshes.  I import the mesh into second life.  When I apply the texture,I apply it to the bottom mesh first, then the top.  This