diff --git a/pkgs/pict-pkgs/pict-doc/pict/scribblings/tree-layout.scrbl b/pkgs/pict-pkgs/pict-doc/pict/scribblings/tree-layout.scrbl
index 1d32239e31..ed6aadce10 100644
--- a/pkgs/pict-pkgs/pict-doc/pict/scribblings/tree-layout.scrbl
+++ b/pkgs/pict-pkgs/pict-doc/pict/scribblings/tree-layout.scrbl
@@ -68,9 +68,10 @@ that render them as @racket[pict]s.
                         [#:x-spacing x-spacing (or/c (and/c real? positive?) #f) #f]
                         [#:y-spacing y-spacing (or/c (and/c real? positive?) #f) #f])
          pict?]{
-  Uses a naive layered algorithm to build the tree.
-  It recursively constructs subtrees and then horizontally
-  combines them, aligning them at the tops. Then it places
+  Uses a naive algorithm that ensures that all nodes at a fixed
+  depth are the same vertical distance from the root (dubbed ``layered'').
+  It recursively lays out subtrees and then horizontally
+  combines them, aligning them at their tops. Then it places
   the root node centered over the children nodes.
   
   @examples[#:eval 
@@ -102,7 +103,9 @@ that render them as @racket[pict]s.
                (tree-layout
                 (tree-layout
                  (tree-layout
-                  (tree-layout #f #f)
+                  (tree-layout 
+                   (tree-layout #f #f)
+                   #f)
                   #f)
                  #f)
                 #f)))
@@ -132,6 +135,12 @@ that render them as @racket[pict]s.
   as it can, even to the point that one subtree of a given node might cross
   under the other one.
 
+  More precisely, it recursively lays out the two subtree and then,
+  without adjusting the layout of the two subtrees, moves them as
+  close together as it can, putting the root of the new tree centered
+  on top of its children. (It does this in linear time, using clever
+  techniques as discussed in the paper.)
+  
   The @racket[x-spacing] and @racket[y-spacing] are the amount of space that each
   row and each column takes up, measured in pixels. If @racket[x-spacing] is @racket[#f],
   it is the width of the widest node @racket[pict?] in the tree. 
diff --git a/pkgs/pict-pkgs/pict-lib/pict/private/naive-layered.rkt b/pkgs/pict-pkgs/pict-lib/pict/private/naive-layered.rkt
index fb3e0129aa..3ad38c6ed7 100644
--- a/pkgs/pict-pkgs/pict-lib/pict/private/naive-layered.rkt
+++ b/pkgs/pict-pkgs/pict-lib/pict/private/naive-layered.rkt
@@ -19,7 +19,9 @@
             (define children-pairs
               (for/list ([child (in-list children)])
                 (match child
-                  [#f (cons #f (blank))]
+                  [#f 
+                   (define b (blank))
+                   (cons b b)]
                   [(tree-edge child color) 
                    (loop child)])))
             (define this-root (launder (ghost pict)))
@@ -106,7 +108,9 @@
      (_tree-layout
       (_tree-layout
        (_tree-layout
-        (_tree-layout #f #f)
+        (_tree-layout 
+         (_tree-layout #f #f)
+         #f)
         #f)
        #f)
       #f)))