diff --git a/OpenRA.Mods.Common/AI/HackyAI.cs b/OpenRA.Mods.Common/AI/HackyAI.cs
index 5817c60151..c02bcf87cb 100644
--- a/OpenRA.Mods.Common/AI/HackyAI.cs
+++ b/OpenRA.Mods.Common/AI/HackyAI.cs
@@ -264,6 +264,7 @@ namespace OpenRA.Mods.Common.AI
 		public Player Player { get; private set; }
 
 		readonly DomainIndex domainIndex;
+		readonly ResourceLayer resLayer;
 		readonly ResourceClaimLayer claimLayer;
 		readonly IPathFinder pathfinder;
 
@@ -311,6 +312,7 @@ namespace OpenRA.Mods.Common.AI
 				return;
 
 			domainIndex = World.WorldActor.Trait<DomainIndex>();
+			resLayer = World.WorldActor.TraitOrDefault<ResourceLayer>();
 			claimLayer = World.WorldActor.TraitOrDefault<ResourceClaimLayer>();
 			pathfinder = World.WorldActor.Trait<IPathFinder>();
 
@@ -667,7 +669,8 @@ namespace OpenRA.Mods.Common.AI
 			if (--assignRolesTicks <= 0)
 			{
 				assignRolesTicks = Info.AssignRolesInterval;
-				GiveOrdersToIdleHarvesters();
+				if (resLayer != null && !resLayer.IsResourceLayerEmpty)
+					GiveOrdersToIdleHarvesters();
 				FindNewUnits(self);
 				FindAndDeployBackupMcv(self);
 			}
diff --git a/OpenRA.Mods.Common/Traits/World/ResourceLayer.cs b/OpenRA.Mods.Common/Traits/World/ResourceLayer.cs
index 4d1c84ce07..4e4f923bf3 100644
--- a/OpenRA.Mods.Common/Traits/World/ResourceLayer.cs
+++ b/OpenRA.Mods.Common/Traits/World/ResourceLayer.cs
@@ -36,7 +36,10 @@ namespace OpenRA.Mods.Common.Traits
 		protected readonly CellLayer<CellContents> Content;
 		protected readonly CellLayer<CellContents> RenderContent;
 
+		public bool IsResourceLayerEmpty { get { return resCells < 1; } }
+
 		bool disposed;
+		int resCells;
 
 		public ResourceLayer(Actor self)
 		{
@@ -217,6 +220,7 @@ namespace OpenRA.Mods.Common.Traits
 		CellContents CreateResourceCell(ResourceType t, CPos cell)
 		{
 			world.Map.CustomTerrain[cell] = world.Map.Rules.TileSet.GetTerrainIndex(t.Info.TerrainType);
+			++resCells;
 
 			return new CellContents
 			{
@@ -255,6 +259,7 @@ namespace OpenRA.Mods.Common.Traits
 			{
 				Content[cell] = EmptyCell;
 				world.Map.CustomTerrain[cell] = byte.MaxValue;
+				--resCells;
 			}
 			else
 				Content[cell] = c;
@@ -270,6 +275,8 @@ namespace OpenRA.Mods.Common.Traits
 			if (Content[cell].Type == null)
 				return;
 
+			--resCells;
+
 			// Clear cell
 			Content[cell] = EmptyCell;
 			world.Map.CustomTerrain[cell] = byte.MaxValue;