Margined White (Pieris marginalis) is a medium-sized butterfly, with a wingspan of 1.5 to 2.25 inches. It is one of the earliest butterflies to fly in our local area.  It can be seen February through early July.  Numbers show a slight peak in March, and then fall off after April. Like the Cabbage White and Checkered White, it has many host plants in the Mustard (Brassicaceae) family.

The upper side of the spring form has black tips on the forewing, and the underside has veins strongly edged with gray-green on the hindwing and the apex of the forewing. The summer form is almost all-white, both above and below. 

This butterfly, like all butterflies in the Pieridae family (Whites and Sulphurs), flies endlessly and does not land very often. So it is under-represented in photograph-based databases like iNaturalist.

It is found primarily in the western US and southern British Columbia. There are also scattered sightings in a narrow coastal belt north from British Columbia through Alaska. The range stretches from British Columbia and Alberta south to central California and southern New Mexico, and east to eastern Wyoming and eastern Colorado.