diff --git a/src/HarvestEffects.cs b/src/HarvestEffects.cs
index 810c2d6..be4a037 100644
--- a/src/HarvestEffects.cs
+++ b/src/HarvestEffects.cs
@@ -194,8 +194,8 @@ public static void ReduceLayers(string prescriptionName, Site site)
 
             // Structural litter
 
-            double carbonLoss = SiteVars.SurfaceStructural[site].Carbon * litterLossMultiplier;
-            double nitrogenLoss = SiteVars.SurfaceStructural[site].Nitrogen * litterLossMultiplier;
+            double carbonLoss = Math.Round(SiteVars.SurfaceStructural[site].Carbon * litterLossMultiplier, 2);
+            double nitrogenLoss = Math.Round(SiteVars.SurfaceStructural[site].Nitrogen * litterLossMultiplier, 2);
 
             SiteVars.SurfaceStructural[site].Carbon -= carbonLoss;
             SiteVars.SourceSink[site].Carbon        += carbonLoss;
@@ -205,8 +205,8 @@ public static void ReduceLayers(string prescriptionName, Site site)
 
             // Metabolic litter
 
-            carbonLoss = SiteVars.SurfaceMetabolic[site].Carbon * litterLossMultiplier;
-            nitrogenLoss = SiteVars.SurfaceMetabolic[site].Nitrogen * litterLossMultiplier;
+            carbonLoss = Math.Round(SiteVars.SurfaceMetabolic[site].Carbon * litterLossMultiplier, 2);
+            nitrogenLoss = Math.Round(SiteVars.SurfaceMetabolic[site].Nitrogen * litterLossMultiplier, 2);
 
             SiteVars.SurfaceMetabolic[site].Carbon  -= carbonLoss;
             SiteVars.SourceSink[site].Carbon        += carbonLoss;
@@ -215,8 +215,8 @@ public static void ReduceLayers(string prescriptionName, Site site)
             SiteVars.SourceSink[site].Nitrogen        += nitrogenLoss;
 
             // Surface dead wood
-            carbonLoss   = SiteVars.SurfaceDeadWood[site].Carbon * woodLossMultiplier;
-            nitrogenLoss = SiteVars.SurfaceDeadWood[site].Nitrogen * woodLossMultiplier;
+            carbonLoss   = Math.Round(SiteVars.SurfaceDeadWood[site].Carbon * woodLossMultiplier, 2);
+            nitrogenLoss = Math.Round(SiteVars.SurfaceDeadWood[site].Nitrogen * woodLossMultiplier, 2);
 
             SiteVars.SurfaceDeadWood[site].Carbon   -= carbonLoss;
             SiteVars.SourceSink[site].Carbon        += carbonLoss;
@@ -226,8 +226,8 @@ public static void ReduceLayers(string prescriptionName, Site site)
 
             // Soil Organic Matter (Duff)
 
-            carbonLoss = SiteVars.SOM1surface[site].Carbon * som_Multiplier;
-            nitrogenLoss = SiteVars.SOM1surface[site].Nitrogen * som_Multiplier;
+            carbonLoss = Math.Round(SiteVars.SOM1surface[site].Carbon * som_Multiplier, 2);
+            nitrogenLoss = Math.Round(SiteVars.SOM1surface[site].Nitrogen * som_Multiplier, 2);
 
             SiteVars.SOM1surface[site].Carbon -= carbonLoss;
             SiteVars.SourceSink[site].Carbon += carbonLoss;
diff --git a/src/Layer.cs b/src/Layer.cs
index 575b54a..d8bdb6f 100644
--- a/src/Layer.cs
+++ b/src/Layer.cs
@@ -352,7 +352,6 @@ public void DecomposeMetabolic(ActiveSite site)
         //---------------------------------------------------------------------
         public void TransferCarbon(Layer destination, double netCFlow)
         {
-
             if (netCFlow < 0)
             {
                 //PlugIn.ModelCore.UI.WriteLine("NEGATIVE C FLOW!  Source: {0},{1}; Destination: {2},{3}.", this.Name, this.Type, destination.Name, destination.Type);
@@ -360,10 +359,11 @@ public void TransferCarbon(Layer destination, double netCFlow)
 
             if (netCFlow > this.Carbon)
                 netCFlow = this.Carbon;
-                //PlugIn.ModelCore.UI.WriteLine("C FLOW EXCEEDS SOURCE!  Source: {0},{1}; Destination: {2},{3}.", this.Name, this.Type, destination.Name, destination.Type);
+            //PlugIn.ModelCore.UI.WriteLine("C FLOW EXCEEDS SOURCE!  Source: {0},{1}; Destination: {2},{3}.", this.Name, this.Type, destination.Name, destination.Type);
 
-            this.Carbon -= netCFlow;
-            destination.Carbon += netCFlow;
+            //round these to avoid unexpected behavior
+            this.Carbon = Math.Round(this.Carbon - netCFlow);
+            destination.Carbon = Math.Round(destination.Carbon + netCFlow);
 
         }