PfSense to apply DNS to different subnets on LAN

[BlueToast]

I would like to apply 4.2.2.1 as the DNS to 10.0.0.x, but OpenDNS to 10.0.39.x and 10.0.40.x; how do I go about doing this? One server acts as a DHCPd server and has my Foxtrot server (different server) set as the router in dhcpd.conf.. like this:

subnet 10.0.0.0 netmask 255.255.0.0 { option routers PfsenseServerIP }

[jimp]

Unless you are assigning those DNS servers directly to clients in those subnets with DHCP, it can't be done in that way. The DNS forwarder can't pick and choose which upstream server to use for clients in that way.