diff --git a/programs/tree.rb b/programs/tree.rb
index 16b536f..ff0e83f 100644
--- a/programs/tree.rb
+++ b/programs/tree.rb
@@ -16,7 +16,7 @@ def draw
   for xIndex in 0..width
     y = 0
     
-    color = (xIndex == 4) ? "green" : "white"
+    color = xIndex.even? ? "green" : "red"
     fill(color)
 
     for yIndex in 0..height