Calochortus monophyllus is a species of flowering plant in the lily family known by the common name yellow star-tulip. It is native to the foothills of the Sierra Nevada and southernmost Cascades in California, its range probably extending north just into Oregon. It is a perennial herb producing a slender, sometimes branched stem up to about 20 centimeters tall. The basal leaf is 10 to 30 centimeters in length and does not wither at flowering. There...