Can biomass be made into a fertilizer?

Yes, biomass can be made into fertilizer.

Specifically, biomass includes renewable and recyclable organic matter formed through photosynthesis. It therefore involves food and food products; plants and plant residues and by-products; and trees and forest products as well as fresh and saltwater algae and plants. Additionally, it refers to nitrogen fixing bacteria and phosphorus fixing bacteria and fungi. Any and all of the above-mentioned biomasses serves as fertilizer.