The unique conditions created by the maritime climate and the Zayante sand soils in the Santa Cruz Sandhills give rise to biological communities found nowhere else in the world. Amidst the variation observed in community composition the Sandhills, two main communities have been described: Northern Maritime Chaparral with Silverleaf Manzanita, and Maritime Coast Range Ponderosa Pine Forest. These communities are known locally as 'sand chaparral' and 'sand parkland', respectively.
Sand chaparral is dominated by shrubs including Santa Cruz Mountains manzanita, buck brush, and silverleaf manzanita, which is endemic to the Sandhills. Sand chaparral also contains scattered trees, including short-statured coast live oaks and two species of pine: knobcone and ponderosa. Within the gaps in the shrub and tree canopy, sand chaparral supports numerous herbaceous plants, including several species of Navarettia, everlasting nest-straw, Santa Cruz monkeyflower, and the Ben Lomond spineflower, which is also endemic to the Sandhills.
Sand chaparral is home to many animals, including pileated woodpeckers, brush rabbits, and two sandhills endemic animals: the Mount Hermon June beetle and the Santa Cruz kangaroo rat.
Located predominantly on steep ridges within the Santa Cruz Sandhills, sand parkland is characterized by a sparse canopy of ponderosa pines surrounded by a diverse assemblage of subshrubs and herbaceous plants. Sand parkland contains the highest diversity and abundance of rare and unique plant species, including the three herbs endemic to the Sandhills: the Ben Lomond spineflower, Santa Cruz wallflower, and Ben Lomond buckwheat.
Sand parkland is also home to the sandhills endemic insects: the Mount Hermon June beetle and Zayante band-winged grasshopper. In addition, sand parkland contains populations of the coast horned lizard and western whiptail lizard, which are far away from the next nearest populations.
Sand parkland is an extraordinarily rare community, occurring on fewer than 200 acres in the world.
