diff --git a/src/definition/VegetationDefinition.cpp b/src/definition/VegetationDefinition.cpp
index 9437560..845a8fa 100644
--- a/src/definition/VegetationDefinition.cpp
+++ b/src/definition/VegetationDefinition.cpp
@@ -13,6 +13,23 @@ VegetationDefinition::VegetationDefinition(DefinitionNode* parent) :
 {
 }
 
+double VegetationDefinition::getMaxHeight() const
+{
+    double max_height = 0.0;
+    int n = count();
+
+    for (int i = 0; i < n; i++)
+    {
+        double layer_height = getVegetationLayer(i)->getMaxHeight();
+        if (layer_height > max_height)
+        {
+            max_height = layer_height;
+        }
+    }
+
+    return max_height;
+}
+
 void VegetationDefinition::applyPreset(VegetationPreset preset)
 {
     VegetationLayerDefinition *layer;
diff --git a/src/definition/VegetationDefinition.h b/src/definition/VegetationDefinition.h
index aea9e11..9480a0a 100644
--- a/src/definition/VegetationDefinition.h
+++ b/src/definition/VegetationDefinition.h
@@ -21,6 +21,11 @@ public:
      */
     inline VegetationLayerDefinition* getVegetationLayer(int position) const {return (VegetationLayerDefinition*)getLayer(position);}
 
+    /**
+     * Get the max height of all layers assembled.
+     */
+    double getMaxHeight() const;
+
     typedef enum
     {
         VEGETATION_PRESET_TEMPERATE
diff --git a/src/definition/VegetationLayerDefinition.cpp b/src/definition/VegetationLayerDefinition.cpp
index 79e53fa..f906f44 100644
--- a/src/definition/VegetationLayerDefinition.cpp
+++ b/src/definition/VegetationLayerDefinition.cpp
@@ -10,6 +10,11 @@ VegetationLayerDefinition::VegetationLayerDefinition(DefinitionNode* parent) :
     presence = new VegetationPresenceDefinition(this);
 }
 
+double VegetationLayerDefinition::getMaxHeight() const
+{
+    return presence->getMaxHeight();
+}
+
 void VegetationLayerDefinition::applyPreset(VegetationLayerPreset preset)
 {
     model->randomize();
diff --git a/src/definition/VegetationLayerDefinition.h b/src/definition/VegetationLayerDefinition.h
index 8fe775b..6a9e41d 100644
--- a/src/definition/VegetationLayerDefinition.h
+++ b/src/definition/VegetationLayerDefinition.h
@@ -19,6 +19,8 @@ public:
     inline const VegetationPresenceDefinition *getPresence() const {return presence;}
     inline const VegetationModelDefinition *getModel() const {return model;}
 
+    double getMaxHeight() const;
+
     typedef enum
     {
         VEGETATION_BASIC_TREES
diff --git a/src/definition/VegetationPresenceDefinition.cpp b/src/definition/VegetationPresenceDefinition.cpp
index f45b301..c77e7d0 100644
--- a/src/definition/VegetationPresenceDefinition.cpp
+++ b/src/definition/VegetationPresenceDefinition.cpp
@@ -19,6 +19,16 @@ VegetationPresenceDefinition::VegetationPresenceDefinition(VegetationLayerDefini
 
 bool VegetationPresenceDefinition::collectInstances(std::vector<VegetationInstance> *result, const VegetationModelDefinition &model, double xmin, double zmin, double xmax, double zmax, bool outcomers) const
 {
+    if (outcomers)
+    {
+        // Expand the area to include outcoming instances
+        double max_radius = getMaxHeight();
+        xmin -= max_radius;
+        zmin -= max_radius;
+        xmax += max_radius;
+        zmax += max_radius;
+    }
+
     bool added = 0;
 
     const NoiseGenerator *generator = noise->getGenerator();
@@ -46,3 +56,8 @@ bool VegetationPresenceDefinition::collectInstances(std::vector<VegetationInstan
 
     return added > 0;
 }
+
+double VegetationPresenceDefinition::getMaxHeight() const
+{
+    return 0.3;
+}
diff --git a/src/definition/VegetationPresenceDefinition.h b/src/definition/VegetationPresenceDefinition.h
index 776c21f..8983c3f 100644
--- a/src/definition/VegetationPresenceDefinition.h
+++ b/src/definition/VegetationPresenceDefinition.h
@@ -27,6 +27,8 @@ public:
      */
     bool collectInstances(std::vector<VegetationInstance> *result, const VegetationModelDefinition &model, double xmin, double zmin, double xmax, double zmax, bool outcomers=true) const;
 
+    double getMaxHeight() const;
+
 private:
     NoiseNode *noise;
     FloatNode *interval;
diff --git a/src/interface/commandline/tests.cpp b/src/interface/commandline/tests.cpp
index 10d04cd..b6ad79b 100644
--- a/src/interface/commandline/tests.cpp
+++ b/src/interface/commandline/tests.cpp
@@ -295,10 +295,14 @@ static void testVegetationModels()
     renderer.setSize(width, height);
     renderer.setQuality(0.5);
 
-    VegetationModelDefinition model(NULL);
-    renderer.setSoloRasterizer(new TestRasterizer(&renderer, model));
+    for (int i = 0; i < 10; i++)
+    {
+        // TODO Make random sequence repeatable
+        VegetationModelDefinition model(NULL);
+        renderer.setSoloRasterizer(new TestRasterizer(&renderer, model));
 
-    startTestRender(&renderer, "vegetation_model_basic");
+        startTestRender(&renderer, "vegetation_model_basic", i);
+    }
 }
 
 void runTestSuite()
diff --git a/src/render/software/VegetationRenderer.cpp b/src/render/software/VegetationRenderer.cpp
index 89ff530..a04dff2 100644
--- a/src/render/software/VegetationRenderer.cpp
+++ b/src/render/software/VegetationRenderer.cpp
@@ -101,18 +101,18 @@ RayCastingResult VegetationRenderer::getResult(const SpaceSegment &segment, bool
 
 RayCastingResult VegetationRenderer::getBoundResult(const SpaceSegment &segment, double x, double z, bool only_hit, double xsize, double zsize)
 {
+    VegetationDefinition *vegetation = parent->getScenery()->getVegetation();
+
     // Early check if we may cross any vegetation
     double ymin, ymax;
-    double vegetation_max_height = 0.0;  // TODO
     parent->getTerrainRenderer()->estimateMinMaxHeight(x, z, x + xsize, z + zsize, &ymin, &ymax);
-    ymax += vegetation_max_height;
+    ymax += vegetation->getMaxHeight();
     SpaceSegment bbox(Vector3(x, ymin, z), Vector3(x + xsize, ymax, z + zsize));
     if (not segment.intersectBoundingBox(bbox)) {
         return RayCastingResult();
     }
 
     // Iterate all layers and instances
-    VegetationDefinition *vegetation = parent->getScenery()->getVegetation();
     int n = vegetation->count();
     for (int i = 0; i < n; i++)
     {