diff --git a/CarbonCalculation.cs b/CarbonCalculation.cs
index 707d264..c48f6c1 100644
--- a/CarbonCalculation.cs
+++ b/CarbonCalculation.cs
@@ -568,9 +568,9 @@ namespace FarmMapsAPI.Carbon
                     var valueList = new List<ColumnValue>();
                     foreach (var stubbleKeyValue in stubbleC.Value)
                     {
-                        var dmYieldValue = dm_Yield_Field[stubbleC.Key].Single(s => s.Key == stubbleKeyValue.Key);
-                        var strawYieldValue = strawYield[stubbleC.Key].Single(s => s.Key == stubbleKeyValue.Key);
-                        var dmContentStraw = cropSet.StrawCrops.Single(s => s.StrawCrop == stubbleKeyValue.Key);
+                        var dmYieldValue = dm_Yield_Field[stubbleC.Key].Single(s => s.Key.ToLower() == stubbleKeyValue.Key.ToLower());
+                        var strawYieldValue = strawYield[stubbleC.Key].Single(s => s.Key.ToLower() == stubbleKeyValue.Key.ToLower());
+                        var dmContentStraw = cropSet.StrawCrops.Single(s => s.StrawCrop.ToLower() == stubbleKeyValue.Key.ToLower());
 
                         var result = ((dmYieldValue.Value + ((stubbleKeyValue.Value + strawYieldValue.Value) * dmContentStraw.DM_Content)) * parameterSet.CarbonBiomass) / ((1 / parameterSet.FracBelowGroundCinput) - 1);
                         valueList.Add(new ColumnValue(stubbleKeyValue.Key, result));
@@ -613,7 +613,7 @@ namespace FarmMapsAPI.Carbon
                             {
                                 result = 12000;
                             }
-                            carbonInputs.AddValue((cropArea.Key.Item1, cropArea.Key.Item2, crop.Key), "CarbonResidues", result);
+                            carbonInputs.AddOrUpdateValue((cropArea.Key.Item1, cropArea.Key.Item2, crop.Key), "CarbonResidues", result);
                         }
                     }
                 }
diff --git a/Models/GamsParameter.cs b/Models/GamsParameter.cs
index 48a69d0..5d98372 100644
--- a/Models/GamsParameter.cs
+++ b/Models/GamsParameter.cs
@@ -34,6 +34,25 @@ namespace FarmMapsAPI.Carbon.Models
             }
         }
 
+        public void AddOrUpdateValue((string, int, string) key, string column, double value)
+        {
+            if (TrippleKeyParam.ContainsKey(key))
+            {
+                if (TrippleKeyParam[key].Any(x => x.Key == column))
+                {
+                    TrippleKeyParam[key].Single(x => x.Key == column).Value = value;
+                }
+                else
+                {
+                    TrippleKeyParam[key].Add(new ColumnValue(column, value));
+                }
+            }
+            else
+            {
+                TrippleKeyParam.Add(key, new List<ColumnValue> { new ColumnValue(column, value) });
+            }
+        }
+
         public void AddValueSkipIfColumnExists((string, int, string) key, string column, double value)
         {
             if (TrippleKeyParam.ContainsKey(key))
diff --git a/config/CropSets.json b/config/CropSets.json
index 3bbc864..52b6d11 100644
--- a/config/CropSets.json
+++ b/config/CropSets.json
@@ -4,6 +4,10 @@
       "StrawCrop": "Maize",
       "DM_Content": 0.7
     },
+    {
+      "StrawCrop": "Fodder_maize",
+      "DM_Content": 0.85
+    },
     {
       "StrawCrop": "Corn_cob_mix",
       "DM_Content": 0.7