Silage additive prepared from crop waste raw materials and use method of silage additive

The invention relates to the field of feed additives, and particularly discloses a silage additive prepared from waste crop raw materials, the silage additive comprises 30-40 parts of compound bacterial powder, 35-45 parts of compound enzyme powder, 15-20 parts of nutrients and 5-8 parts of an auxiliary compound, and a use method of the silage additive comprises the following steps: S1, raw material pretreatment; s2, dissolving the biological additive; s3, spraying; S4, sealing and fermenting; S5, regularly checking; and S6, completing fermentation. The additive is used for preparing silage from waste crop raw materials, structural polysaccharides of the raw materials are preferentially degraded into micromolecular sugars such as monosaccharides or oligosaccharides through a plant cell wall degrading enzyme system, reproduction of compound bacteria is promoted, the fermentation period can be obviously shortened, the fermentation effect can be improved, and the comprehensive utilization value of the plant raw