diff --git a/Translations/locale.xml b/Translations/locale.xml
index a5932f443..524b19b21 100644
--- a/Translations/locale.xml
+++ b/Translations/locale.xml
@@ -106,6 +106,22 @@
 		</strings>
 	</locale>
 
+        <locale>
+		<lang type="string">zh</lang>
+		<lang type="string">zh_CN</lang>
+
+		<strings>
+			<options>Translations/zh_CN/options.xml</options>
+			<!-- Chinese startup tips disabled for now because the
+			     font used to display them in FlightGear's splash
+			     screen doesn't have the required glyphs
+			     (2017-06-25). cf.
+			     https://sourceforge.net/p/flightgear/fgdata/merge-requests/92/
+			-->
+			<!-- <tips>Translations/zh_CN/tips.xml</tips> -->
+		</strings>
+        </locale>
+
 	<locale>
 		<!--  test character encoding using - -language=TEST -->
 		<lang type="string">TEST</lang>
diff --git a/Translations/zh_CN/options.xml b/Translations/zh_CN/options.xml
new file mode 100644
index 000000000..46879219c
--- /dev/null
+++ b/Translations/zh_CN/options.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- FlightGear options: Simplified Chinese language resource -->
+
+<PropertyList>
+</PropertyList>
diff --git a/Translations/zh_CN/tips.xml b/Translations/zh_CN/tips.xml
new file mode 100644
index 000000000..83aa0b21d
--- /dev/null
+++ b/Translations/zh_CN/tips.xml
@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!-- FlightGear startup tips: Simplified Chinese language resource -->
+
+<!-- Style tips: Aim to keep to a single phrase/sentence which is not
+                 terminated with a . -->
+<PropertyList>
+	<tip n="0">在按住鼠标右键时滑动鼠标以观察四周</tip>
+	<tip n="1">在观察四周时按住 [Shift] 来将视角向上、下、左、右移动</tip>
+	<tip n="2">按下 a/A 来调整模拟器速度（倍速）</tip>
+	<tip n="3">按下 x/X 来放大或缩小</tip>
+	<tip n="4">从 Radios 对话框可查询附近ATC频率</tip>
+	<tip n="5">按下 v 来更换视角, 按下 Ctrl-V 可回到驾驶舱视角</tip>
+	<tip n="6">按下 F3 可以截图</tip>
+	<tip n="7">欢迎加入FlightGear社区，网址为 http://forum.flightgear.org</tip>
+	<tip n="8">按下 h 来启用抬头显示器（HUD）</tip>
+	<tip n="9">按下 F10 来隐藏或显示菜单栏</tip>
+	<tip n="10">帧率太低？ - 试试禁用AI交通</tip>
+	<tip n="11">选择 Environment → Weather 在不同天气条件下飞行</tip>
+	<tip n="12">按下F12可轻易更换无线频率</tip>
+	<tip n="13">在按住鼠标右键时滑动鼠标以观察四周</tip>
+	<tip n="14">选择 Multiplayer → Multiplayer Settings 来加入联机飞行</tip>
+	<tip n="15">不知如何启动引擎？ - 查看 Help → Aircraft Checklists</tip>
+	<tip n="16">在按住鼠标右键与中键时滑动鼠标以移动观察点</tip>
+	<tip n="17">按下 / 来浏览FlightGear的内部属性</tip>
+	<tip n="18">按下 Tab 后使用鼠标来移动观察点，并使用滚轮放大或缩小</tip>
+</PropertyList>
diff --git a/gui/dialogs/rendering.xml b/gui/dialogs/rendering.xml
index 773dd26b4..2733c7673 100644
--- a/gui/dialogs/rendering.xml
+++ b/gui/dialogs/rendering.xml
@@ -407,10 +407,13 @@
 					<pref-width>200</pref-width>
 					<property>/sim/gui/dialogs/rendering/random-vegetation</property>
 					<value>Disabled</value>
+					<value>Ultra Low Density</value>
+					<value>Very Low Density</value>
 					<value>Low Density</value>
 					<value>Medium Density</value>
 					<value>High Density</value>
 					<value>Very High Density</value>
+					<value>Ultra High Density</value>
 					<binding>
 						<command>dialog-apply</command>
 						<object-name>random-vegetation</object-name>
@@ -423,6 +426,16 @@
 								setprop("/sim/rendering/random-vegetation", 0);
 							}
 
+							if (val == "Ultra Low Density") {
+								setprop("/sim/rendering/random-vegetation", 1);
+								setprop("/sim/rendering/vegetation-density", 0.1);
+							}
+
+							if (val == "Low Density") {
+								setprop("/sim/rendering/random-vegetation", 1);
+								setprop("/sim/rendering/vegetation-density", 0.25);
+							}
+
 							if (val == "Low Density") {
 								setprop("/sim/rendering/random-vegetation", 1);
 								setprop("/sim/rendering/vegetation-density", 0.5);
@@ -435,12 +448,17 @@
 
 							if (val == "High Density") {
 								setprop("/sim/rendering/random-vegetation", 1);
-								setprop("/sim/rendering/vegetation-density", 4.0);
+								setprop("/sim/rendering/vegetation-density", 2.0);
 							}
 
 							if (val == "Very High Density") {
 								setprop("/sim/rendering/random-vegetation", 1);
-								setprop("/sim/rendering/vegetation-density", 10.0);
+								setprop("/sim/rendering/vegetation-density", 4.0);
+							}
+
+							if (val == "Ultra High Density") {
+								setprop("/sim/rendering/random-vegetation", 1);
+								setprop("/sim/rendering/vegetation-density", 8.0);
 							}
 
 						</script>
@@ -1077,14 +1095,27 @@
 
 			if (getprop("/sim/rendering/random-vegetation")) {
 				var density = getprop("/sim/rendering/vegetation-density");
-				if (density < 0.99) {
+				if (density < 0.2) {
+					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Ultra Low Density");
+					# 0.1
+				} else if (density < 0.4) {
+					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Very Low Density");
+					# 0.25
+				} else if (density < 0.8) {
 					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Low Density");
-				} else if (density < 1.99) {
+					# 0.5
+				} else if (density < 1.5) {
 					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Medium Density");
-				} else if (density < 4.01) {
+					# 1.0
+				} else if (density < 3.0) {
 					setprop("/sim/gui/dialogs/rendering/random-vegetation", "High Density");
-				} else {
+					# 2.0
+				} else if (density < 6.0) {
 					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Very High Density");
+					# 4.0
+				} else {
+					setprop("/sim/gui/dialogs/rendering/random-vegetation", "Ultra High Density");
+					# 8.0
 				}
 			} else {
 				setprop("/sim/gui/dialogs/rendering/random-vegetation", "Disabled");