diff --git a/lib/client/chart.js b/lib/client/chart.js
index c48bfdf80f6..9a604e8f959 100644
--- a/lib/client/chart.js
+++ b/lib/client/chart.js
@@ -164,6 +164,9 @@ function init (client, d3, $) {
     .tickFormat(d3.format('d'))
     .tickValues(tickValues);
 
+  d3.select('tick')
+    .style('z-index', '10000');
+
   // setup a brush
   chart.brush = d3.brushX()
     .on('start', brushStarted)