diff --git a/src/lib/tree.typ b/src/lib/tree.typ
index ad596d1d2..2e168ce10 100644
--- a/src/lib/tree.typ
+++ b/src/lib/tree.typ
@@ -131,12 +131,20 @@
   }
   assert(draw-node != none, message: "Node draw callback must be set!")
 
-  let build-node(tree, depth: 0, sibling: 0) = {
+  let build-node(tree-arr, depth: 0, sibling: 0) = {
     let children = ()
     let content = none
+
+    let (e, tree) = if type(tree-arr) == array and tree-arr.len() == 2 and type(tree-arr.at(0)) in (int,float) {
+        tree-arr
+    } else {
+        (1, tree-arr)
+    }
+    let depth = depth + e
+
     if type(tree) == array {
       children = tree.slice(1).enumerate().map(
-        ((n, c)) => build-node(c, depth: depth + 1, sibling: n)
+        ((n, c)) => build-node(c, depth: depth, sibling: n)
       )
       content = tree.at(0)
     } else {
diff --git a/tests/tree/test.typ b/tests/tree/test.typ
index 5516753bb..e4c58b3c3 100644
--- a/tests/tree/test.typ
+++ b/tests/tree/test.typ
@@ -42,3 +42,8 @@
   })
   h(.1cm)
 }
+
+#test-case({
+  // Specify branch lengths
+  cetz.tree.tree(([], (1, ([], (1, []), (1, []))), (2, [])))
+})