diff --git a/builtin/describe.c b/builtin/describe.c
index c428984706..e4869df7b4 100644
--- a/builtin/describe.c
+++ b/builtin/describe.c
@@ -502,7 +502,7 @@ static void describe(const char *arg, int last_one)
 
 	if (cmit)
 		describe_commit(&oid, &sb);
-	else if (lookup_blob(&oid))
+	else if (sha1_object_info(oid.hash, NULL) == OBJ_BLOB)
 		describe_blob(oid, &sb);
 	else
 		die(_("%s is neither a commit nor blob"), arg);
diff --git a/t/t6120-describe.sh b/t/t6120-describe.sh
index a5d9015024..bae78c4e89 100755
--- a/t/t6120-describe.sh
+++ b/t/t6120-describe.sh
@@ -378,4 +378,12 @@ check_describe tags/A --all A
 check_describe tags/c --all c
 check_describe heads/branch_A --all --match='branch_*' branch_A
 
+test_expect_success 'describe complains about tree object' '
+	test_must_fail git describe HEAD^{tree}
+'
+
+test_expect_success 'describe complains about missing object' '
+	test_must_fail git describe $_z40
+'
+
 test_done