Index: clear_cmd.c
===================================================================
--- clear_cmd.c	(revision 4073)
+++ clear_cmd.c	(working copy)
@@ -655,9 +655,14 @@
 				SetClearCounter(tile, 0);
 			}
 
-			field_type = GetFieldType(tile);
-			field_type = (field_type < 8) ? field_type + 1 : 0;
-			SetFieldType(tile, field_type);
+			if (_m[tile].m2 == 0xFFFF) {
+				/* Remove field */
+				MakeClear(tile, CL_GRASS, 0);
+			} else {
+				field_type = GetFieldType(tile);
+				field_type = (field_type < 8) ? field_type + 1 : 0;
+				SetFieldType(tile, field_type);
+			}
 			break;
 		}
 
Index: industry_cmd.c
===================================================================
--- industry_cmd.c	(revision 4073)
+++ industry_cmd.c	(working copy)
@@ -880,6 +880,18 @@
 		}
 	END_TILE_LOOP(tile_cur, i->width, i->height, i->xy);
 
+	if (i->type == IT_FARM || i->type == IT_FARM_2) {
+		/* Clear our ID from our farmland */
+		/* This should only really clear the area around the farm, not the whole map */
+		BEGIN_TILE_LOOP(tile_cur, MapSizeX(), MapSizeY(), 0);
+		if (IsTileType(tile_cur, MP_CLEAR) && IsClearGround(tile_cur, CL_FIELDS)) {
+			if (_m[tile_cur].m2 == i->index) {
+				_m[tile_cur].m2 = 0xFFFF;
+			}
+		}
+		END_TILE_LOOP(tile_cur, MapSizeX(), MapSizeY(), 0);
+	}
+
 	i->xy = 0;
 	_industry_sort_dirty = true;
 	DeleteSubsidyWithIndustry(i->index);
@@ -928,7 +940,7 @@
 	} while (--size);
 }
 
-static void PlantFarmField(TileIndex tile)
+static void PlantFarmField(TileIndex tile, uint16 industry)
 {
 	uint size_x, size_y;
 	uint32 r;
@@ -968,7 +980,7 @@
 	BEGIN_TILE_LOOP(cur_tile, size_x, size_y, tile)
 		cur_tile = TILE_MASK(cur_tile);
 		if (!IsBadFarmFieldTile2(cur_tile)) {
-			MakeField(cur_tile, field_type);
+			MakeField(cur_tile, field_type, industry);
 			SetClearCounter(cur_tile, counter);
 			MarkTileDirtyByTile(cur_tile);
 		}
@@ -991,7 +1003,7 @@
 		int x = i->width  / 2 + Random() % 31 - 16;
 		int y = i->height / 2 + Random() % 31 - 16;
 		TileIndex tile = TileAddWrap(i->xy, x, y);
-		if (tile != INVALID_TILE) PlantFarmField(tile);
+		if (tile != INVALID_TILE) PlantFarmField(tile, i->index);
 	}
 }
 
@@ -1490,7 +1502,7 @@
 			int y = Random() % 31 - 16;
 			TileIndex new_tile = TileAddWrap(tile, x, y);
 
-			if (new_tile != INVALID_TILE) PlantFarmField(new_tile);
+			if (new_tile != INVALID_TILE) PlantFarmField(new_tile, i->index);
 		}
 	}
 	_industry_sort_dirty = true;
Index: clear_map.h
===================================================================
--- clear_map.h	(revision 4073)
+++ clear_map.h	(working copy)
@@ -56,11 +56,11 @@
 }
 
 
-static inline void MakeField(TileIndex t, uint field_type)
+static inline void MakeField(TileIndex t, uint field_type, uint16 industry)
 {
 	SetTileType(t, MP_CLEAR);
 	SetTileOwner(t, OWNER_NONE);
-	_m[t].m2 = 0;
+	_m[t].m2 = industry;
 	_m[t].m3 = field_type;
 	_m[t].m4 = 0 << 5 | 0 << 2;
 	SetClearGroundDensity(t, CL_FIELDS, 3);