The Firesafe Council has provided a special needs assistance program in the past and is currently working on securing funds for a future program. Updates will be posted here and at their website http://www.areyoufiresafe.com/
The Nevada County Resource Conservation District has some programs for larger property owners that can help offset vegetation mitigation costs. Find info on their website here: http://www.ncrcd.org/ Additionally 211 is a free service that can connect you to community resources and services that may be appropriate for your situation. Dial 2-1-1 or 1-833-DIAL211 for assistance.