Table 3.2. Percent occurrence of the more abundant species in the transition from upland to 

 wetland at the northernmost part of Tijuana Estuary. Data are from 0.25 m 2 circular quadrats 

 (numbers sampled in parentheses) taken per 40-cm elevation class (Zedler unpubl. data). 



Elevation Class 3 

 Species 



1 2 3 4 5 6 7 8 91011 

 (29) (99) (52) (25) (33) (30) (31) (34) (22) (33) ( 8 ) 



Artemisia californica 

 Eriogonum fasciculatum 

 Haplopappus venetus 

 Rhus laurina 

 Atriplex semibaccata 

 Cressa truxillensis 

 Distichlis spicata 

 Frankenia grandifolia 

 Lycium californicum 

 Monanthochloe littoralis 

 Salicornia subterminalis 

 Salicornia virginica 

 Limonium californicum 

 Atriplex watsonii 



27 



1 2 



27 39 75 



a Elevation classes each included a 40-cm (16-inch) elevation range; they are numbered 

 from low to high elevation. 



The marsh species that grows highest up 

 the slope is saltgrass (Distichlis spicata). 

 Also found in sandy areas near the dunes, this 

 marsh plant is easily mistaken for Bermuda 

 grass (Cynodon dactylon) in vegetative form. 

 Insects, however, know the difference. The 

 saltgrass is the sole host plant for larvae of 

 the wandering skipper (Panoquina errans, 

 Lepidoptera: Hesperidae; Figure 3.1). The 

 first occurrences of alkali weed (Cressa 

 truxillensis) and alkali heath are additional 

 indicators that you have moved from the 

 upland down into the wetland. At the sloped 

 corner, they first appear at approximately 3 

 m (9.2 ft) above MSL. While the habitat 

 where the highest marsh plants occur is often 

 dry, it becomes inundated when storms 

 coincide with the highest spring tides (Cayan 

 and Flick 1985). 



Figure 3.1. 

 mm long. 

 Zedler. 



The wandering skipper. Body 14 

 Mclntire collection, © 1986 by 



27 



