diff --git a/imsg.h b/imsg.h
index b84be86f..43a29282 100644
--- a/imsg.h
+++ b/imsg.h
@@ -18,8 +18,6 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-#include <sys/tree.h>
-
 #define READ_BUF_SIZE		65535
 #define IMSG_HEADER_SIZE	sizeof(struct imsg_hdr)
 #define MAX_IMSGSIZE		16384