diff --git a/forms/TreeDropdownField.php b/forms/TreeDropdownField.php
index 52d1718a2..ef5583c93 100644
--- a/forms/TreeDropdownField.php
+++ b/forms/TreeDropdownField.php
@@ -132,6 +132,13 @@ class TreeDropdownField extends FormField {
 		return $this->showSearch;
 	}
 
+	/**
+	 * @param Boolean
+	 */
+	public function setShowSearch($bool) {
+		$this->showSearch = $bool;
+	}
+
 	/**
 	 * @return string
 	 */