diff --git a/README.md b/README.md
index cb740151c..d7dbd137e 100644
--- a/README.md
+++ b/README.md
@@ -285,6 +285,14 @@ We're going to try spinning this out into its own library; see: https://github.c
             include: ['mapknitter', 'clouds'],
          }).addTo(map);
 
+## Add base layers:
+
+    L.LayerGroup.EnvironmentalLayers({
+            baseLayers: {               // Grayscale base map is used by default when this is undefined 
+             'Standard': baselayer1
+            },
+          }).addTo(map);
+
 ## Turn on Leaflet Hash in the URL:
 
 	 L.LayerGroup.EnvironmentalLayers({
diff --git a/dist/LeafletEnvironmentalLayers.js b/dist/LeafletEnvironmentalLayers.js
index 28b6b04ff..a2013999e 100644
--- a/dist/LeafletEnvironmentalLayers.js
+++ b/dist/LeafletEnvironmentalLayers.js
@@ -25855,6 +25855,9 @@ L.LayerGroup.environmentalLayers = L.LayerGroup.extend(
       hash: false,
       embed: false, // activates layers on map by default if true.
       currentHash: location.hash,
+      defaultBaseLayer: L.tileLayer('https://a.tiles.mapbox.com/v3/jywarren.map-lmrwb2em/{z}/{x}/{y}.png', {
+        attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
+      }),
       // Source of Truth of Layers name .
       // please put name of Layers carefully in the the appropriate layer group.
       layers0: ['purpleLayer', 'toxicReleaseLayer', 'pfasLayer', 'aqicnLayer', 'osmLandfillMineQuarryLayer', 'Unearthing'],
@@ -25914,7 +25917,7 @@ L.LayerGroup.environmentalLayers = L.LayerGroup.extend(
     onAdd: function(map) {
       this._map = map;
       this.overlayMaps = {};
-      var baseMaps = this.options.baseLayers;
+      var baseMaps = this.options.baseLayers ? this.options.baseLayers : { "Grey-scale": this.options.defaultBaseLayer.addTo(map) };
 
       for (let layer of this.options.layers.include) {
         if (this.options.layers0.includes(layer)) {
diff --git a/example/oneLinerCodeExample.html b/example/oneLinerCodeExample.html
index 1d0b62bc1..3e9edddc5 100644
--- a/example/oneLinerCodeExample.html
+++ b/example/oneLinerCodeExample.html
@@ -61,13 +61,13 @@
       }).setView([43, -83], 3);
       map.options.minZoom = 3;
 
-      var baselayer1 =L.tileLayer(
-            "https://a.tiles.mapbox.com/v3/jywarren.map-lmrwb2em/{z}/{x}/{y}.png",
-            {
-              attribution:
-                '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
-            }
-          ).addTo(map);
+      var baselayer1 = L.tileLayer(
+        'https://api.tiles.mapbox.com/v4/mapbox.emerald/{z}/{x}/{y}.png?access_token=pk.eyJ1Ijoic2FnYXJwcmVldDk3IiwiYSI6ImNqaXhlZjgwaDJtb3EzcW1zdDdwMzJkODcifQ.MA2YIv6VpGLLAo-QYUudTA',
+        {
+          attribution:
+                  '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
+        },
+      ).addTo(map);
 
       /* This is required, make this optional! */
       // var oms = omsUtil(map, {
@@ -75,9 +75,9 @@
       //   circleSpiralSwitchover: 0
       // });
       L.LayerGroup.EnvironmentalLayers({
-        baseLayers: {
-          'Grey-scale': baselayer1
-        },
+        // baseLayers: {
+        //   'Standard': baselayer1
+        // },
         include: ['odorreport', 'asian', 'clouds', 'eonetFiresLayer', 'Unearthing'],
         // exclude: ['mapknitter', 'clouds'],
         hash: true,
diff --git a/package.json b/package.json
index 893d74fa5..98266fa8e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "leaflet-environmental-layers",
-  "version": "2.1.7",
+  "version": "2.1.8",
   "description": "",
   "main": "index.js",
   "directories": {
diff --git a/src/AllLayers.js b/src/AllLayers.js
index cbe06cca3..f5d5e33d7 100644
--- a/src/AllLayers.js
+++ b/src/AllLayers.js
@@ -5,6 +5,9 @@ L.LayerGroup.environmentalLayers = L.LayerGroup.extend(
       hash: false,
       embed: false, // activates layers on map by default if true.
       currentHash: location.hash,
+      defaultBaseLayer: L.tileLayer('https://a.tiles.mapbox.com/v3/jywarren.map-lmrwb2em/{z}/{x}/{y}.png', {
+        attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
+      }),
       // Source of Truth of Layers name .
       // please put name of Layers carefully in the the appropriate layer group.
       layers0: ['purpleLayer', 'toxicReleaseLayer', 'pfasLayer', 'aqicnLayer', 'osmLandfillMineQuarryLayer', 'Unearthing'],
@@ -64,7 +67,7 @@ L.LayerGroup.environmentalLayers = L.LayerGroup.extend(
     onAdd: function(map) {
       this._map = map;
       this.overlayMaps = {};
-      var baseMaps = this.options.baseLayers;
+      var baseMaps = this.options.baseLayers ? this.options.baseLayers : { "Grey-scale": this.options.defaultBaseLayer.addTo(map) };
 
       for (let layer of this.options.layers.include) {
         if (this.options.layers0.includes(layer)) {