  We study the response of EJ-301 liquid scintillator to monochromatic 244.6
$\pm$ 8.4 keV neutrons, targeting the 10-100 keV proton recoil energy interval.
Limited experimental information exists for proton light yield in this range,
for this or any other organic scintillator. Our results confirm the adequacy of
a modified Birks' model, common to all organic scintillator formulations,
predicting a marked increase in quenching factor as proton energy approaches
the few keV regime. The relevance of this behavior within the context of
searches for low-mass particle dark matter is mentioned.
