Try to focus on that green blur in front of a blossom, perhaps a Blue Dicks flower (Dichelostemma capitatum) or vetch (Genus Vicia). Is it a hummingbird? Perhaps. But it may be a Clark’s Sphinx moth too! 

This time of the year (from March to June), they are flying about the oak woodland and surrounding grasslands from flower to flower, drinking flower nectar from a variety of flowers. It moves so quickly to another flower, uncurling its long proboscis to reach into flowers. They are not abundant, but I see them nearly every year.

Clark’s Sphinx moths have a greenish forewing and an orange hindwing that has a black band along its base. Clark’s Sphinx range from Baja California north to British Columbia, and east to Idaho, Wyoming and Utah, and can be found in Oak woodland foothills.

They lay eggs on Elegant Clarkia (Clarkia unguiculata), the sole host plant that their caterpillars feed on. The eggs hatch in about 10 days, and once fully grown, the caterpillars pupate in burrows dug under rocks or other objects. They overwinter there and emerge the following Spring.

I hope you see one!