The study looked at how Astragalus membranaceus plants absorb nitrogen, phosphorus, and potassium at different growth stages. They found that the plant accumulates the most dry matter between 100-163 days after sprouting. Nitrogen absorption is highest, followed by potassium and then phosphorus. The plant needs 2.32 kg of nitrogen, 0.323 kg of phosphorus, and 1.62 kg of potassium to produce 100 kg of Astragalus membranaceus.