diff --git a/unmaintained/trees/authors.txt b/extra/trees/authors.txt
similarity index 100%
rename from unmaintained/trees/authors.txt
rename to extra/trees/authors.txt
diff --git a/unmaintained/trees/avl-tree/avl-tree-tests.factor b/extra/trees/avl-tree/avl-tree-tests.factor
similarity index 100%
rename from unmaintained/trees/avl-tree/avl-tree-tests.factor
rename to extra/trees/avl-tree/avl-tree-tests.factor
diff --git a/unmaintained/trees/avl-tree/avl-tree.factor b/extra/trees/avl-tree/avl-tree.factor
similarity index 100%
rename from unmaintained/trees/avl-tree/avl-tree.factor
rename to extra/trees/avl-tree/avl-tree.factor
diff --git a/unmaintained/trees/bst/bst-tests.factor b/extra/trees/bst/bst-tests.factor
similarity index 100%
rename from unmaintained/trees/bst/bst-tests.factor
rename to extra/trees/bst/bst-tests.factor
diff --git a/unmaintained/trees/bst/bst.factor b/extra/trees/bst/bst.factor
similarity index 100%
rename from unmaintained/trees/bst/bst.factor
rename to extra/trees/bst/bst.factor
diff --git a/unmaintained/trees/summary.txt b/extra/trees/summary.txt
similarity index 100%
rename from unmaintained/trees/summary.txt
rename to extra/trees/summary.txt
diff --git a/unmaintained/trees/tags.txt b/extra/trees/tags.txt
similarity index 100%
rename from unmaintained/trees/tags.txt
rename to extra/trees/tags.txt
diff --git a/unmaintained/trees/trees.factor b/extra/trees/trees.factor
similarity index 100%
rename from unmaintained/trees/trees.factor
rename to extra/trees/trees.factor