Seed collection and processing of wildland showy milkweed (Asclepias speciosa)

Abstract

Demand for seed of native milkweed species (Asclepias L. [Asclepiadaceae]) is increasing because of numerous factors including growing emphasis on native pollinator habitat in restoration seedings, increased awareness of beneficial insects associated with milkweed, and recent declines in monarch butterfly (Danaus plexippus L. [Lepidoptera: Nymphalidae]) populations. Showy milkweed (A. speciosa Torr.) may be particularly important to the migration and life cycle of the western monarch population as it is the most abundant milkweed species in the arid West where monarchs lay eggs during the summer months. However, locally sourced, agricultural-scale seed production of milkweeds for conservation use is extremely rare. Wildland harvesting from native stands is a viable alternative where large populations of milkweed are present in canal-driven irrigation systems and wetlands in the West. Small, low-tech seed collection operations have the potential to gather significant quantities of locally adapted seed for use in conservation projects in a sustainable manner. This article describes a few simple techniques we have found to be successful for the collection and processing of showy milkweed seed.