Merge branch 'master' into jgrpp-beta

# Conflicts:
#	src/lang/chuvash.txt
#	src/lang/czech.txt
#	src/lang/english_AU.txt
#	src/lang/english_US.txt
#	src/lang/german.txt
#	src/lang/japanese.txt
#	src/lang/korean.txt
#	src/lang/latvian.txt
#	src/lang/russian.txt
#	src/tree_gui.cpp
#	src/vehicle.cpp

src/tree_cmd.cpp

@@ -449,9 +449,10 @@ void RemoveAllTrees()
  * @param treetype  Type of trees to place. Must be a valid tree type for the climate.
  * @param radius    Maximum distance (on each axis) from tile to place trees.
  * @param count     Maximum number of trees to place.
+ * @param set_zone  Whether to create a rainforest zone when placing rainforest trees.
  * @return Number of trees actually placed.
  */
-uint PlaceTreeGroupAroundTile(TileIndex tile, TreeType treetype, uint radius, uint count)
+uint PlaceTreeGroupAroundTile(TileIndex tile, TreeType treetype, uint radius, uint count, bool set_zone)
 {
 	assert(treetype < TREE_TOYLAND + TREE_COUNT_TOYLAND);
 	const bool allow_desert = treetype == TREE_CACTUS;
@@ -482,6 +483,12 @@ uint PlaceTreeGroupAroundTile(TileIndex tile, TreeType treetype, uint radius, ui
 		}
 	}
 
+	if (set_zone && IsInsideMM(treetype, TREE_RAINFOREST, TREE_CACTUS)) {
+		for (TileIndex t : TileArea(tile).Expand(radius)) {
+			if (GetTileType(t) != MP_VOID && DistanceSquare(tile, t) < radius * radius) SetTropicZone(t, TROPICZONE_RAINFOREST);
+		}
+	}
+
 	return planted;
 }