diff --git a/app/ModelFilters/CropYieldFilter.php b/app/ModelFilters/CropYieldFilter.php
index 76b2c6f..2b3fe27 100644
--- a/app/ModelFilters/CropYieldFilter.php
+++ b/app/ModelFilters/CropYieldFilter.php
@@ -17,4 +17,11 @@ class CropYieldFilter extends ModelFilter
     {
         return $this->where('crop_id', $cropId);
     }
+
+    public function type($type)
+    {
+        return $this->whereHas('base', function($q) use ($type) {
+            return $q->where('type', $type);
+        });
+    }
 }