The reproductive cycle of soapweed depends exclusively upon the lifecycle of its pollinator, the yucca moth. See:
- Adult female yucca moths actively collect pollen from one soapweed plant, then usually fly to another. Upon finding a fresh
flower, a female first inserts her ovipositor through the carpel wall and lays an egg next to the developing ovules.
- She then climbs to the tip of the style, and using her maxillary tentacles (appendages unique to yucca moths), she actively
transfers pollen into the stylar canal, pollinating the plant.
- There is no other consistently successful mechanism of pollen transfer, and yucca moth larvae feed only on yucca seeds.
Soapweed is classified as At Risk in the General Status of Alberta Wild Species report. See:
Soapweed is currently listed as Endangered under the Wildlife Act. For more information on this species and the
assessment and listing process, see:
For more information on this species, see the Status of Soapweed in Alberta report at:
- The success of Alberta soapweed populations is heavily dependant upon the success of yucca moth populations. Along with
the soapweed, the yucca moth has also been recommended for listing as Endangered under the Wildlife Act.
- Other factors limiting the success of soapweed populations include:
- Habitat fragmentation due to agricultural activity
- Reduction of plants due to high winds or cattle and wild ungulate grazing
- Harvesting of soapweed for human horticultural and medicinal uses
A joint recovery plan for soapweed and yucca moth has been was developed and is under implementation. For details, see:
Research is ongoing in Alberta regarding soapweed and yucca moth interaction to better understand the mutual relationship
and establish appropriate management measures.
Updated: Mar 4, 2014