Wool and Hair Waste as Nutrient Source for High-value Crops

The study conducted one small-plot field and five container experiments to assess the use of sheep wool and human hair waste as soil amendments for high-value crops. The addition of wool or hair waste to soil increased crop yields, enhanced secondary metabolite production, and raised NH4-N and NO3-N levels in the soil, as well as total nitrogen and protein content in plant tissues. It did not affect soil microbial biomass but decreased mycorrhizae colonization. Despite not fully decomposing, the wool and hair retained significant sulfur and some nitrogen. The findings suggested that a single addition of 0.33% wool or hair waste by weight could support two to five harvests without additional fertilizers, potentially improving soil biological and chemical properties.