diff --git a/american-journal-of-botany.csl b/american-journal-of-botany.csl
index c84340df318..b6d8a879034 100644
--- a/american-journal-of-botany.csl
+++ b/american-journal-of-botany.csl
@@ -109,7 +109,7 @@
       </else>
     </choose>
   </macro>
-  <citation et-al-min="3" et-al-use-first="1" disambiguate-add-year-suffix="true" disambiguate-add-names="true" collapse="year-suffix">
+  <citation et-al-min="3" et-al-use-first="1" disambiguate-add-year-suffix="true" disambiguate-add-names="false" collapse="year-suffix">
     <sort>
       <key macro="year-date"/>
     </sort>