diff --git a/conf/e2/terrains.json b/conf/e2/terrains.json
index 709f1b1a4..470bc8b7c 100644
--- a/conf/e2/terrains.json
+++ b/conf/e2/terrains.json
@@ -229,21 +229,21 @@
             "production": {
                 "iron": {
                     "chance": 0.5,
-                    "level": 1,
-                    "base": 50,
-                    "div": 50
+                    "level": "1",
+                    "base": "50",
+                    "div": "50"
                 },
                 "stone": {
                     "chance": 0.5,
-                    "level": 1,
-                    "base": 100,
-                    "div": 100
+                    "level": "1",
+                    "base": "100",
+                    "div": "100"
                 },
                 "laen": {
                     "chance": 0.075,
-                    "level": 1,
-                    "base": 4,
-                    "div": 100
+                    "level": "1",
+                    "base": "4",
+                    "div": "100"
                 }
             }
         },
@@ -254,21 +254,21 @@
             "production": {
                 "iron": {
                     "chance": 0.5,
-                    "level": 1,
-                    "base": 50,
-                    "div": 50
+                    "level": "1",
+                    "base": "50",
+                    "div": "50"
                 },
                 "stone": {
                     "chance": 0.5,
-                    "level": 1,
-                    "base": 100,
-                    "div": 100
+                    "level": "1",
+                    "base": "100",
+                    "div": "100"
                 },
                 "laen": {
                     "chance": 0.075,
-                    "level": 1,
-                    "base": 4,
-                    "div": 100
+                    "level": "1",
+                    "base": "4",
+                    "div": "100"
                 }
             }
         },
diff --git a/src/kernel/jsonconf.c b/src/kernel/jsonconf.c
index 64ae06477..c8126715a 100644
--- a/src/kernel/jsonconf.c
+++ b/src/kernel/jsonconf.c
@@ -192,32 +192,38 @@ static void json_terrain_production(cJSON *json, terrain_production *prod) {
     assert(json->type == cJSON_Object);
     cJSON *child;
     for (child = json->child; child; child = child->next) {
+        char **dst = 0;
         switch (child->type) {
-        case cJSON_String:
-            if (strcmp(child->string, "base") == 0) {
-                prod->base = _strdup(child->valuestring);
-            }
-            else if (strcmp(child->string, "level") == 0) {
-                prod->startlevel = _strdup(child->valuestring);
-            }
-            else if (strcmp(child->string, "div") == 0) {
-                prod->divisor = _strdup(child->valuestring);
-            }
-            else {
-                log_error("terrain_production %s contains unknown attribute %s", json->string, child->string);
-            }
-            break;
         case cJSON_Number:
             if (strcmp(child->string, "chance") == 0) {
                 prod->chance = (float)child->valuedouble;
             }
             else {
-                log_error("terrain_production %s contains unknown attribute %s", json->string, child->string);
+                log_error("terrain_production %s contains unknown number %s", json->string, child->string);
+            }
+            break;
+        case cJSON_String:
+            if (strcmp(child->string, "base") == 0) {
+                dst = &prod->base;
+            }
+            else if (strcmp(child->string, "level") == 0) {
+                dst = &prod->startlevel;
+            }
+            else if (strcmp(child->string, "div") == 0) {
+                dst = &prod->divisor;
+            }
+            else {
+                log_error("terrain_production %s contains unknown string %s", json->string, child->string);
             }
             break;
         default:
             log_error("terrain_production %s contains unknown attribute %s", json->string, child->string);
         }
+        if (dst) {
+            free(*dst);
+            assert(child->type == cJSON_String);
+            *dst = _strdup(child->valuestring);
+        }
     }
 }