Linux – HAProxy seems to be load balancing instead of following ACL rules

I'm seeing some really odd behavior with HAProxy. I have the following setup below designed to allow example.com/wiki to go to one server and example.com/ go to another. The trouble is that it seems like the /wiki only works half the time and the / webserver only works half the time as well. Upon closer examination, it seems like it's switching between the two backends; possibly load balancing them, instead of going to a specific backend based on the ACL rules!

Another oddity is that both services-staging.example.com/greenoven and staging.example.com both would go to kumquat, even though the rules specifically say that only the services-staging host should go to that backend.

Is something wrong with my HAProxy configuration? Am I using acls or backends incorrectly?

global
        log 127.0.0.1   local1 debug
        maxconn 200000
        chroot /var/lib/haproxy
        user haproxy
        group haproxy
        daemon
        #debug
        #quiet

defaults
        log     global
        mode    http
        option  httplog
        option  dontlognull
        retries 3
        option redispatch
        maxconn 200000
        contimeout      5000
        clitimeout      50000
        srvtimeout      50000

        stats uri /monitor
        stats auth admin:GS01
        stats refresh 5s
        stats enable


frontend http-in
        bind *:80

        option forwardfor

        #Staging Hosts

        acl host_staging hdr(host) -i staging.example.com
        acl host_staging_services hdr(host) -i staging-services.example.com

        #Production Hosts

        acl host_prod hdr(host) -i example.com www.example.com
        acl host_prod_services hdr(host) -i services.urbanatla.com

        #URL Paths

        acl url_wiki url_beg /wiki
        acl url_go   url_beg /greenoven
        acl url_arcgis url_beg /ArcGIS

        #Staging Backends

        use_backend pluto if host_staging_services url_arcgis
        use_backend kumquat if host_staging_services url_go
        use_backend kumquat if host_staging url_wiki
        use_backend cumberland if host_staging

        #Production Backends

        use_backend saturn if host_prod_services url_arcgis
        use_backend willow if host_prod_services url_go
        use_backend willow if host_prod url_wiki
        use_backend ganges if host_prod


backend kumquat
        server kumquat kumquat.example.com:8080 maxconn 5000

backend cumberland
        server cumberland cumberland.example.com:80 maxconn 5000

backend ganges
        server ganges ganges.example.com:80 maxconn 5000

backend articdata
        server articdata  articdata.example.com:80 maxconn  5000

backend saturn
        server saturn saturn.example.com:80 maxconn 5000

backend willow
        server willow willow.example.com:8080 maxconn 5000

backend pluto
        server pluto pluto.example.com:80 maxconn 5000