diff --git a/CHANGELOG.md b/CHANGELOG.md
index f2c04ae0..9415e6c4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,7 +14,7 @@ and this project adheres to Rust's notion of
   - `FullViewingKey::scope_for_address`
 
 ### Changed
-- Migrated to `halo2_proofs 0.1.0-beta.4`.
+- Migrated to `halo2_proofs 0.1.0-beta.4`, `incrementalmerkletree 0.3.0-beta.2`.
 - `orchard::builder`:
   - `Builder::add_spend` now requires that the `FullViewingKey` matches the
     given `Note`, and handles any scoping itself (instead of requiring the
diff --git a/Cargo.toml b/Cargo.toml
index 6d6bd981..2ac8329c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -41,7 +41,7 @@ nonempty = "0.7"
 serde = { version = "1.0", features = ["derive"] }
 subtle = "2.3"
 zcash_note_encryption = "0.1"
-incrementalmerkletree = "=0.3.0-beta.1"
+incrementalmerkletree = "=0.3.0-beta.2"
 
 # Developer tooling dependencies
 plotters = { version = "0.3.0", optional = true }
diff --git a/src/builder.rs b/src/builder.rs
index 5808c67a..ae2df0ac 100644
--- a/src/builder.rs
+++ b/src/builder.rs
@@ -690,9 +690,9 @@ pub mod testing {
             for note in notes.iter() {
                 let leaf = MerkleHashOrchard::from_cmx(&note.commitment().into());
                 tree.append(&leaf);
-                let (position, leaf) = tree.witness().expect("tree is not empty");
+                let position = tree.witness().expect("tree is not empty");
 
-                let path = MerklePath::from((position, tree.authentication_path(position, &leaf).expect("we just witnessed the path")));
+                let path = MerklePath::from((position, tree.authentication_path(position).expect("we just witnessed the path")));
                 notes_and_auth_paths.push((*note, path));
             }
 
diff --git a/src/tree.rs b/src/tree.rs
index 874d08e0..dd01af7e 100644
--- a/src/tree.rs
+++ b/src/tree.rs
@@ -283,7 +283,8 @@ pub mod testing {
         {
             let cmx = MerkleHashOrchard::from_bytes(&tv.leaves[i]).unwrap();
             tree.append(&cmx);
-            tree.witness().expect("tree is not empty");
+            let position = tree.witness().expect("tree is not empty");
+            assert_eq!(position, i.into());
 
             assert_eq!(tree.root().0, pallas::Base::from_repr(tv.root).unwrap());
 
@@ -291,9 +292,8 @@ pub mod testing {
             // for not-yet-appended leaves (using UNCOMMITTED_ORCHARD as the leaf value),
             // but BridgeTree doesn't encode these.
             for j in 0..=i {
-                let leaf = MerkleHashOrchard::from_bytes(&tv.leaves[j]).unwrap();
                 assert_eq!(
-                    tree.authentication_path(j.try_into().unwrap(), &leaf),
+                    tree.authentication_path(j.try_into().unwrap()),
                     Some(
                         tv.paths[j]
                             .iter()
diff --git a/tests/builder.rs b/tests/builder.rs
index c7496f9f..9f89ec7d 100644
--- a/tests/builder.rs
+++ b/tests/builder.rs
@@ -74,8 +74,8 @@ fn bundle_chain() {
         let leaf = MerkleHashOrchard::from_cmx(&cmx);
         let mut tree = BridgeTree::<MerkleHashOrchard, 32>::new(0);
         tree.append(&leaf);
-        let (position, leaf) = tree.witness().unwrap();
-        let auth_path = tree.authentication_path(position, &leaf).unwrap();
+        let position = tree.witness().unwrap();
+        let auth_path = tree.authentication_path(position).unwrap();
         let merkle_path = MerklePath::from_parts(
             u64::from(position).try_into().unwrap(),
             auth_path[..].try_into().unwrap(),