Spartina alterniflora x foliosa hybrids scorecard

2197
Impact
SpreadNotesScore
Spread Rate Grows rapidly by natural spread, both by underground tiller growth and by seed dispersal. 4
Spread Amount Hybrids are more vigorous and reproductively fit than either of the parents. S. alterniflora and in cases such as SF Bay - seem to be the primary colonizer. 4
DamageNotesScore
Ecological Threat to the survival of the native S. foliosa and threatened species, loss of species diversity, conversion of mudflat to meadow, can impact newly restored areas. Rated high in the Cal-IPC Inventory 5
Agricultural Can threaten oyster growing operations. 1
Infrastructure Increased rates of sedimentation, leading to the eventual clogging of flood control channels and natural sloughs, raising them to the overall elevation of the marsh plain. 2
Cultural Changes to landscape, bird and fish use diminished bird watching and fishing impacted. 2
Health Creates mosquito breeding areas. 3
BenefitNotesScore
Ecological Very productive plant that can be a major source of carbon. 1
Agricultural 0
Infrastructure Can help to stabilize sediments in some locations. 1
Cultural 0
Benefit Health 0
Ability to Respond
Ease of ResponseNotesScore
Detection S. alterniflora- foliosa hybrids may be confused with the native S. foliosa and with brackish marsh plant Scirpus maritimus (alkalai bulrush) or Triglochin maritima (arrow grass). 3
Control Requires detecated funding and staff to perform eradication . May require various treatment methods (i.e digging and herbicide ) and may require follow-up treatment for multiple years. 1
Tools in PlaceNotesScore
Entry Some barriers in place. Non-native Spartina is no longer used in restoration. In CA non-native spartina is currently under review for listing as noxious. 3
Control Strong response from local, Federal and State agencies to fund eradication. Ongoing control efforts in California and Washington aimed at strategies that minimize export of seeds and vegetative propagules. 4
Outreach Taxonomic refereces available via websites and literature, on-going workshops, ability to call in new reports of infestations. On Cal-IPC list. 3
Scorecard Totals
Impact Total:
19
[Impact] = ([Spread] + [Damage] - [Benefit])
Ability to Respond Total:
14
[Ability to Respond] = ([Ease of Response] + [Tools in Place])
Confidence
Confidence:  high
Notes:
Sources: