I am thinking the 14x Mhz was probably left-over from the Military [Arsenal] days, as the USFW uses 162-174 Mhz, altho there could still be a DoD Cooperative on-going for some of the still sensative sites?
I still hear traffic on the 148.9 repeater whenever I monitor it. Not really interesting most of the time. There may be other freqs, but I haven't really looked for them.