Distribution and Abundance of Salt Marsh Dodder (Cuscuta salina) at Elkhorn Slough

Katie Alt Griffith

Ocean Sciences Department

Salt Marsh Plant Zonation

• Abiotic Factors

• Biotic Factors

How would a parasitic plant be distributed in a salt marsh as a function of its host?

• Holoparasite

• Preferred Host

• Native!

Salicornia

Cuscuta

Cuscuta salina: a parasitic plant

1. How does Cuscuta distribution correlate with abiotic factors in Elkhorn Slough?

• Elevation

WRACK

• Wrack

• Flow Regime

• Land Use

2. What are the mechanisms involved in distributional patterns?

WRACK

• Seed dispersal

• Germination

• Seedling survival

3. How does nitrogen supply affect this host-parasite interaction?

Testing the

Plant Vigor

Hypothesis

Fertilized Not Fertilized

1

2

3

4

5

6

7

8

Cuscuta

Bio

mas

s (g

dry

wei

ght)

Salicornia

P = 0.001

n = 20

UNFERTILIZED

FERTILIZED

Is Cuscuta more abundant in marshes that receive inputs of synthetic fertilizers??

3. How does nitrogen supply affect this host-parasite interaction?

• How much nitrogen in tissues?

• Source of nitrogen?

• Level of infection / spread?

• Contribute to our knowledge of pattern and process in salt marsh plant zonation

• Provide insight to how this native plant functions in its wetland environment, both naturally and in response to ecological encroachments

Significance