diff --git a/lib/ancestry/class_methods.rb b/lib/ancestry/class_methods.rb
index 58abbeae..514a9b2f 100644
--- a/lib/ancestry/class_methods.rb
+++ b/lib/ancestry/class_methods.rb
@@ -200,15 +200,5 @@ def rebuild_depth_cache!
     def unscoped_where
       yield self.ancestry_base_class.unscope(:where)
     end
-
-    ANCESTRY_UNCAST_TYPES = [:string, :uuid, :text].freeze
-
-    def primary_key_is_an_integer?
-      if defined?(@primary_key_is_an_integer)
-        @primary_key_is_an_integer
-      else
-        @primary_key_is_an_integer = !ANCESTRY_UNCAST_TYPES.include?(type_for_attribute(primary_key).type)
-      end
-    end
   end
 end
diff --git a/test/concerns/has_ancestry_test.rb b/test/concerns/has_ancestry_test.rb
index b48aa000..26f1fa78 100644
--- a/test/concerns/has_ancestry_test.rb
+++ b/test/concerns/has_ancestry_test.rb
@@ -123,16 +123,4 @@ def test_setup_test_nodes
       end
     end
   end
-
-  def test_primary_key_is_an_integer
-    AncestryTestDatabase.with_model(extra_columns: { string_id: :string }) do |model|
-      model.primary_key = :string_id
-
-      assert !model.primary_key_is_an_integer?
-    end
-
-    AncestryTestDatabase.with_model do |model|
-      assert model.primary_key_is_an_integer?
-    end
-  end
 end