Eriophyllum lanatum, also known as Oregon sunshine, has 810000 seeds per pound. Native to western North America, commonly growing in many dry, open places below 10,000 feet (3,000 m) in elevation. It prefers full sun and well-drained soil, but it also grows on rocky slopes and bluffs. It is most common across California, in chaparral, oak woodland, mixed evergreen forest, and yellow pine forest and other conifer forests, grassland, and sagebrush scrub habitats. 
More Info: USDA Plant Guide: https://plants.usda.gov/DocumentLibrary/plantguide/pdf/pg_erla6.pdf