To explore the susceptibility of herbaceous plants to delignification with hydrotropic liquors, the pulping of Miscanthus, oat hulls, and intermediate flax straw was performed with a concentrated sodium benzoate solution. The main characteristics of pulp samples derived hydrotropically from Miscanthus, oat hulls, and intermediate flax straw are given. Miscanthus was found to be more susceptible to delignification, with a pulp yield of 45% and lignin content of 7%. For oat hulls, the pulp yield is 31% and lignin content 9%. The cooking of intermediate flax straw affords a pulp in 51% yield but the lignin content is as high as 17%; further studies are needed. The pulps obtained from Miscanthus and oat hulls were confirmed by infrared spectroscopy.