Unity 5 transparency in custom shader


i cannot seem to wrap my head around it since converting the project to unity 5 every transparency shader hasn’t worked or got some weird background transparency on the trees.

Here’s a pic from my grass billboard :

And here’s the shader code for that grass billboard :

Shader "Partner/Billboard_alpha_to_coverage" {
	Properties {
		_Color ("Color", Color) = (1,1,1,1)
		_MainTex ("Albedo (RGB)", 2D) = "white" {}
		_Brightness ("Brightness override", range (0,25.0)) = 0.0
		Tags {"Queue"="Transparent"}
		LOD 200
		Blend SrcAlpha OneMinusSrcAlpha
		AlphaToMask On
		Cull Off
		// Physically based Standard lighting model, and enable shadows on all light types
		#pragma surface surf BlinnPhong alpha
		//#pragma target 3.0

		sampler2D _MainTex;
		float _Brightness;

		struct Input {
			float2 uv_MainTex;

		fixed4 _Color;

		void surf (Input IN, inout SurfaceOutput o) {
			// Albedo comes from a texture tinted by color
			fixed4 c = tex2D (_MainTex, IN.uv_MainTex) * _Color;
			o.Albedo = c.rgb * _Brightness;
			o.Alpha = c.a;
	FallBack "Diffuse"

You probably need to add a tag “RenderType” = “Transparent”
That said, I can’t get transparency to work even with that …