Roots are called "coralloid" with an "Anabaena" symbiosis allowing nitrogen fixation. Symbiotic blue-green algae are also found in the coralloid (i.e. upward growing) roots. Structures like this are called tuberculate or coralloid ectomycorrhizas. As in other cycads, "S. eriopus" forms coralloid roots. Coralloid roots are just like lateral roots, but highly specialized to contain cyanobacteria.