"One pound of boron increased yield. Limestone and boron interactively affected clover yield. Clover production was not significantly increased by fine limestone when boron was absent. Clover yield was increased by one pound of boron per acre applied to plots treated with fine limestone." 1
1- Haby, Villavicencio, Davis and Leonard. 1990. Rose Clover Response to Limestone and Boron. p. 46-50. Texas Agricultural Experiment Station. Tech. Report No. 90-1.