NOVELTY - Slow release fertilizer synergistic agent comprises boric acid (5-8 pts. wt.), oxalic acid (3-4 pts. wt.), calcium superphosphate (2-5 pts. wt.), pine sawdust (23-25 pts. wt.), rapeseed cake (28-32 pts. wt.), dried vegetables (14-15 pts. wt.), wood sugar (10-12 pts. wt.), and slow release microorganism layer (2-4 pts. wt.), slow release chelated microelement layer (4-5 pts. wt.), slow release microcrystalline phosphorus ore powder (6-9 pts. wt.), and water.    USE - Slow release fertilizer synergistic agent used for providing nutrients to corn (claimed).    ADVANTAGE - The slow release fertilizer synergistic agent prevents caking of soil and fertilizer, promotes corn growth, and improves fertilizer utilization rate, and has large surface area.    DETAILED DESCRIPTION - Slow release fertilizer synergistic agent comprises boric acid (5-8 pts. wt.), oxalic acid (3-4 pts. wt.), calcium superphosphate (2-5 pts. wt.), pine sawdust (23-25 pts. wt.), rapeseed cake (28-32 pts. wt.), dried vegetables (14-15 pts. wt.), wood sugar (10-12 pts. wt.), and slow release microorganism layer (2-4 pts. wt.), slow release chelated microelement layer (4-5 pts. wt.), slow release microcrystalline phosphorus ore powder (6-9 pts. wt.), and water. Slow release microbial layer comprises Effective Microorganisms (RTM: common species of anaerobic organisms found in all environments) (5-7 pts. wt.), diatomite (45-55 pts. wt.), and syrup (120-140 pts. wt.). Effective microorganism is added to syrup under stirring condition. Diatomite is soaked in sulfuric acid solution for 60 minutes. Soaked diatomite is washed to obtain neutral pH. Washed product is dried at 400-500 degrees C for 2-3 hours, and then cool to room temperature. Cooled product is pulverized to obtain fine powder, and then mixed with obtained microbial suspension. Obtained mixture is stirred for 20-30 minutes, and then filtered and air-dried at 30-40 degrees C. Slow release chelated microelement layer comprises attapulgite (24-26 pts. wt.), waste animal fur (16-18 pts. wt.), ferrous sulfate (4-7 pts. wt.), and zinc sulfate (3-5 pts. wt.). Slow release chelated microelement layer is prepared by sintering attapulgite at 600-80 degrees C for 2 hours, and then pulverizing sintered material. Waste animal fur is treated with 6-8 mol/L hydrochloric acid for 18-24 hours. Milk of lime is added to obtained product to maintain pH at 7. Obtained product is filtered, and then mixed with ferrous sulfate and heated at 40-60 degrees C for 1-2 hours. Obtained product is treated with zinc sulfate at 50-80 degrees C for 1.5-3 hours. Obtained product is mixed with attapulgite powder, and then dried and pulverized. Slow release microcrystalline phosphorus layer comprises rock phosphate (28-32 pts. wt.), bone glue (8-10 pts. wt.), and water. Slow release microcrystalline phosphorus layer is prepared by pulverizing rock phosphate, and then adding bone glue and water. Obtained mixture is treated at 70-80 degrees C for 8-10 hours under stirring condition. An INDEPENDENT CLAIM is included for a method for preparing slow release fertilizer synergistic agent, which involves:    (A) adding pine sawdust, rapeseed cake flour, vegetables, and water in compost tank;    (B) fermenting obtained mixture for 3-4 weeks;    (C) pulverizing fermented product;    (D) adding microcrystalline rock phosphate to obtained product;    (E) centrifuging mixture of boric acid, wood sugar and water at 80-120 revolutions/minute for 20 minutes;    (F) drying centrifuged product;    (G) pulverizing calcium phosphate and oxalic acid;    (H) adding water to obtained pulverized product;    (I) mixing obtained product, microbial layer, pulverized fermented product and dried centrifuged product; and    (J) drying obtained mixture at 40-50 degrees C.