diff --git a/src/economy.c b/src/economy.c
index a3b300788..248344e47 100644
--- a/src/economy.c
+++ b/src/economy.c
@@ -2130,7 +2130,7 @@ static void planttrees(unit * u, int raw)
     }
 
     /* Mallornb�ume kann man nur in Mallornregionen z�chten */
-    rtype = get_resourcetype(fval(r, RF_MALLORN) ? R_MALLORNSEED : R_SEED);
+    rtype = get_resourcetype(fval(r, RF_MALLORN) ? R_MALLORN_SEED : R_SEED);
 
     /* Skill pr�fen */
     skill = effskill(u, SK_HERBALISM, 0);
@@ -2195,7 +2195,7 @@ static void breedtrees(unit * u, int raw)
     }
 
     /* Mallornb�ume kann man nur in Mallornregionen z�chten */
-    rtype = get_resourcetype(fval(r, RF_MALLORN) ? R_MALLORNSEED : R_SEED);
+    rtype = get_resourcetype(fval(r, RF_MALLORN) ? R_MALLORN_SEED : R_SEED);
 
     /* Skill pr�fen */
     skill = effskill(u, SK_HERBALISM, 0);
@@ -2313,7 +2313,7 @@ static void breed_cmd(unit * u, struct order *ord)
     default:
         if (p != P_ANY) {
             rtype = findresourcetype(s, u->faction->locale);
-            if (rtype == get_resourcetype(R_SEED) || rtype == get_resourcetype(R_MALLORNSEED)) {
+            if (rtype == get_resourcetype(R_SEED) || rtype == get_resourcetype(R_MALLORN_SEED)) {
                 breedtrees(u, m);
                 break;
             }
diff --git a/src/kernel/item.c b/src/kernel/item.c
index 6e64c147f..58e3326a2 100644
--- a/src/kernel/item.c
+++ b/src/kernel/item.c
@@ -614,25 +614,24 @@ struct order *ord)
 #define R_MINHERB R_PLAIN_1
 #define R_MINPOTION R_FAST
 #define R_MINITEM R_IRON
-#define MAXITEMS MAX_ITEMS
-#define MAXRESOURCES MAX_RESOURCES
-#define MAXHERBS MAX_HERBS
-#define MAXPOTIONS MAX_POTIONS
 #define MAXHERBSPERPOTION 6
 
-const potion_type *oldpotiontype[MAXPOTIONS + 1];
+const potion_type *oldpotiontype[MAX_POTIONS + 1];
 
 /*** alte items ***/
 
 static const char *resourcenames[MAX_RESOURCES] = {
+    "money", "aura", "permaura",
+    "hp", "peasant", "person",
+    "sapling", "mallornsapling", 
+    "tree", "mallorntree",
+    "seed", "mallornseed",
     "iron", "stone", "horse", "ao_healing",
     "aots", "roi", "rop", "ao_chastity",
     "laen", "fairyboot", "aoc", "pegasus",
     "elvenhorse", "charger", "dolphin", "roqf", "trollbelt",
     "aurafocus", "sphereofinv", "magicbag",
-    "magicherbbag", "dreameye", "p2", "seed", "mallornseed",
-    "money", "aura", "permaura",
-    "hp", "peasant", "person"
+    "magicherbbag", "dreameye", "p2"
 };
 
 const resource_type *get_resourcetype(resource_t type) {
@@ -966,7 +965,7 @@ static void init_oldpotions(void)
     };
     int p;
 
-    for (p = 0; p != MAXPOTIONS; ++p) {
+    for (p = 0; p != MAX_POTIONS; ++p) {
         item_type *itype = it_find(potionnames[p]);
         if (itype != NULL) {
             oldpotiontype[p] = itype->rtype->ptype;
@@ -978,6 +977,11 @@ void init_resources(void)
 {
     resource_type *rtype;
 
+    /* there are resources that are special and must be hard-coded.
+     * these are not items, but things like trees or hitpoints
+     * which can be used in a construction recipe or as a spell ingredient.
+     */
+
     rt_get_or_create(resourcenames[R_PERSON]); /* lousy hack */
 
     rtype = rt_get_or_create(resourcenames[R_PEASANT]);
diff --git a/src/kernel/item.h b/src/kernel/item.h
index c1ac38517..c08c676be 100644
--- a/src/kernel/item.h
+++ b/src/kernel/item.h
@@ -252,8 +252,27 @@ extern "C" {
         variant magres, int prot, unsigned int flags);
     potion_type *new_potiontype(item_type * itype, int level);
 
+
+    /* these constants are used with get_resourcetype.
+     * The order of the enum is not important for stored data.
+     * The resourcenames array must be updated to match.
+     */
+
     typedef enum {
+        /* SPECIAL */
+        R_SILVER,
+        R_AURA,                     /* Aura */
+        R_PERMAURA,                 /* Permanente Aura */
+        R_LIFE,
+        R_PEASANT,
+        R_PERSON,
+        R_SAPLING,
+        R_MALLORN_SAPLING,
+        R_TREE,
+        R_MALLORN_TREE,
         /* ITEMS: */
+        R_SEED,
+        R_MALLORN_SEED,
         R_IRON,
         R_STONE,
         R_HORSE,
@@ -277,15 +296,7 @@ extern "C" {
         R_SACK_OF_CONSERVATION,
         R_TACTICCRYSTAL,
         R_WATER_OF_LIFE,
-        R_SEED,
-        R_MALLORNSEED,
         /* SONSTIGE */
-        R_SILVER,
-        R_AURA,                     /* Aura */
-        R_PERMAURA,                 /* Permanente Aura */
-        R_LIFE,
-        R_PEASANT,
-        R_PERSON,
 
         MAX_RESOURCES,              /* do not use outside item.c ! */
         NORESOURCE = -1
diff --git a/src/modules/arena.c b/src/modules/arena.c
index fbc3f0673..aada12234 100644
--- a/src/modules/arena.c
+++ b/src/modules/arena.c
@@ -149,7 +149,7 @@ enter_arena(unit * u, const item_type * itype, int amount, order * ord)
 
     assert(!"not implemented");
     /*
-            for (res=0;res!=MAXRESOURCES;++res) if (res!=R_SILVER && res!=R_ARENA_GATE && (is_item(res) || is_herb(res) || is_potion(res))) {
+            for (res=0;res!=MAX_RESOURCES;++res) if (res!=R_SILVER && res!=R_ARENA_GATE && (is_item(res) || is_herb(res) || is_potion(res))) {
             int x = get_resource(u, res);
             if (x) {
             if (u2) {