MUDDY FEET - Auckland Regional Council

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Wet Carex divisa
This sedge may dominate the edge of the various water bodies, at times covering 70-90% of
these areas, with occasional grasses (Cynodon, Schedonurus.)
Dry Carex divisa
Carex divisa forms scattered patches on dry shell-mud ridges. Other plants in this association
are prickly sowthistle (Sonchus asper), tarweed (Parentucellia vicosa), buck’shorn plantain
(Plantago coronopus) and perennial ryegrass (Lolium perenne).
The impact of the introduced divided sedge (Carex invisa) on the salt marsh ecology was part
of the study by Strahan (1997). Strahan studied the salinity tolerance of this sedge and the
competition between this and other species in the salt marsh. [See section 3.3 Grazing.]
3.1.6 Ryegrass (Lolium)– Bur Medic (Medicago) short grassland
This grassland community is the most abundant over the old shellbanks of the Chenier plain
at Miranda. It occurs on the drier shell/soil substrates, further from the sea but adjacent to the
salt marsh and has the coastal highway going through it. The vegetation is more diverse than
elsewhere but is dominated by introduced species, principally legumes and grasses.
Important elements are sea primrose (Samolus), ox-tongue (Picris), stonecrop (Sedum acre),
viper’s bugloss (Echium), chickweed (Stellaria), dove’s foot (Geranium), plantains
(Plantago), divided sedge (Carex divisa), legumes (Medicago, Trifolium) and grasses (Briza,
Bromus, Catapodium, Cynodon, Hordeum, Lolium, Parapholis, Pennisetum, Polypogon,
Vulpia.)
This is the main area grazed by cattle, which in wetter places is subject to trampling and
pugging. It forms an important part of the Miranda area both for human access and as the
habitat for several introduced birds such as the skylark, which nests in depressions in this
grassland, and seed-eating birds, such as finches.
3.1.7 Saltmarsh Ribbonwood (Plagianthus)– Mingimingi (Coprosma) shrub
This association is only found in a few isolated areas at Miranda but more extensive areas are
found in other parts of the Coast. The salt marsh ribbonwood is a common constituent of salt
marsh and old shellbank vegetation throughout New Zealand. In an area near the Miranda
Stream it is associated with planted tamarisk (Tamarix sp.), but there is also a small roadside
community north of the Shorebird Centre, where it is associated with mingimingi (Coprosma
propinqua) and pohuehue (Muehlenbeckia complexa).
This latter community is also the site for the endangered green mistletoe (Ileostylus
micranthus.) [See section 3.4 Threatened plants of Miranda]
3.2 Survey of the foreshore between Tararu and Hot Springs Drain
Pilot surveys of the foreshore vegetation of the southern part of the Firth of Thames (Tararu
to Hot Springs Drain) were carried out in 1998 and 1999 (6 days total). The observers
travelled mainly along the stop banks, on foot and by quad, from Tararu (north of Thames) to
the Hot Springs Drain at Miranda, and along the beach from Taramaire to Kaiaua. Similar
work was done by kayak in the Piako River, and from Waitakaruru to the Miranda Stream at
high to mid tide. Observations were made for comparison with, and clarification of, colour
aerial photographs (December 1996 series, Figure 1-2, Figure 1-3 and Figure -5-2) from
Tararu to Kaiaua (Figure 1-1). General characteristics and predominant land uses are
described for each of the sections surveyed. The main focus was on broad vegetation types
EcoQuest Education Foundation EQRS/1 12/04