diff --git a/df.materials.xml b/df.materials.xml
index 8199ec45a..105790d6d 100644
--- a/df.materials.xml
+++ b/df.materials.xml
@@ -253,9 +253,9 @@
 
         <df-flagarray name='flags' index-enum='material_flags'/>
 
-        <int16_t name='extract_storage'/>
-        <int16_t name='butcher_special_type'/>
-        <int16_t name='butcher_special_subtype'/>
+        <enum base-type='int16_t' name='extract_storage' type-name='item_type'/>
+        <enum base-type='int16_t' name='butcher_special_type' type-name='item_type'/>
+        <int16_t name='butcher_special_subtype' refers-to='(item-subtype-target $$._parent.butcher_special_type $)'/>
 
         <static-array name='meat_name' type-name='stl-string' count='3'/>
         <static-array name='block_name' type-name='stl-string' count='2'/>