diff --git a/spacy/tests/doc/test_to_json.py b/spacy/tests/doc/test_to_json.py
index 9abe5779d..9ebee6c88 100644
--- a/spacy/tests/doc/test_to_json.py
+++ b/spacy/tests/doc/test_to_json.py
@@ -10,8 +10,16 @@ def doc(en_vocab):
     heads = [0, 0, 0]
     deps = ["ROOT", "dobj", "dobj"]
     ents = ["O", "B-ORG", "O"]
+    morphs = ["Feat1=A", "Feat1=B", "Feat1=A|Feat2=D"]
     return Doc(
-        en_vocab, words=words, pos=pos, tags=tags, heads=heads, deps=deps, ents=ents
+        en_vocab,
+        words=words,
+        pos=pos,
+        tags=tags,
+        heads=heads,
+        deps=deps,
+        ents=ents,
+        morphs=morphs,
     )
 
 
diff --git a/spacy/tokens/doc.pyx b/spacy/tokens/doc.pyx
index 0499dc4a7..4a57e4c83 100644
--- a/spacy/tokens/doc.pyx
+++ b/spacy/tokens/doc.pyx
@@ -1398,8 +1398,6 @@ cdef class Doc:
         attributes. Attribute values need to be JSON-serializable. Values will
         be added to an "_" key in the data, e.g. "_": {"foo": "bar"}.
         RETURNS (dict): The data in spaCy's JSON format.
-
-        DOCS: https://nightly.spacy.io/api/doc#to_json
         """
         data = {"text": self.text}
         if self.has_annotation("ENT_IOB"):
@@ -1421,7 +1419,7 @@ cdef class Doc:
             if include_annotation["POS"]:
                 token_data["pos"] = token.pos_
             if include_annotation["MORPH"]:
-                token_data["morph"] = token.morph_
+                token_data["morph"] = token.morph
             if include_annotation["LEMMA"]:
                 token_data["lemma"] = token.lemma_
             if include_annotation["DEP"]: