The fruit, when dry, usually splits open forcefully, effectively scattering the seeds. I have heard stories of walking along the trails on Montara Mountain while the Lupine are popping, but have yet to experience this. On Montara Mountain, particularly bothersome invasives include Bird's Foot Lotus and the infamous French Broom , species that are so aggressive they inhibit any native vegetation from re-establishing in disturbed areas.
Elimination is advised.
Fabaceae is well represented on Montara Mountain. Tri-foliate leaflets, with margin strongly toothed. Distinct folds along center vein. Round spiny spiral pods that split in half to release seeds. When mature, the spiny seed pods detach and stick to your socks.