EooLOGiCAL Notes on the Vegetation of 80-Mile Beach. 161 
On wluit Mi)pear to be damper patches in the grassland there are colonies 
of EuUdia fulva oi’ Botliriochloa dccipiens (both knoAvn as Bundle Bundle 
Brass) Avith Paniciim decompositum as a subordinant form. 
As a j'ule the grass flats are treeless areas but occasionally there arc 
small grou[)s of Melaleuca leuofiidendron and M. latiiandra (Cadgibut). Herej 
as a ruhg most ot' the grasses are absent, though Cenciirus ciliaris may occur. 
These tree groui)s i'e]>resent isolated [)atches of tlu* Cadgibut shrubland facies 
which forms a definite phase in the transitional zone betAveen the coastal 
plain \egetation and that of the si)inifex pindan. This border type appears 
not only where the Junction is betAveen loam and red sand but also Avhoi’e it 
is between grev and red sand. 
(ii) Samphire flats and clayj>ans occur in the sand hill country as well 
as on the grass flats. The soil is grey loam. Since there is no pi'oper drainage 
system the loam flats are the only places AA'here one Avould expect Avater to 
lie after I’ain. Tracks through these Hats have a sinister reputation for their 
mud during the Avet season. It seems likely that the soil here has a slightly 
higher concentration of mineral salts. If this is so it explains the zonation 
which can be observed. There are three zones. In the outer one Sporoholus 
virgin'eus (Salt Grass form) is dominant and there may be colonies of 
Triantliemii turgidi folia. Other }>lants Avhich have been collected in this zone 
include Tricliinium exaltatnm and Scaevola spinescens. In the next zone 
Trianthema turgidifolia has beconu' dominant. !Mixed Avith it are Bassia 
astrocarpa and Atrijdejc elacliopliylla. In some i)laces either of; these zones 
may carry small thickets of Acaoia hivenosa or Acacia salicina^ but othei’Avise 
trees and shrubs are completely lacking on the samphire flats. Trianthe7na 
turgidifolia is locally known as yelloAv samphire. The third zone sees 
Trianthema turgidifolia replaced by Artlirocnemim Bentlumiii (Red or Black 
Samphire). This species gradually thins out until the bare ground of the 
centre is reached. 
A good example of samphire Hat is seen at Wooroo Creek between the 
sandhills. Tlu‘ portion near the creek, Avhich has a border of mangroves, is 
Hooded at certain times of the year Avhen there are exceptionally high tides. 
Over this portion Trianlhc'iva is replaced by Arthrocnenium Benthamii. 
(c) Cadgibut Shrul)land. 
This s(‘ction represents a peetdiar deA'elopment of the coastal plain. 
Various sp('cies of Melaleuca are abundant and dominat<* the vegetation. 
This is in sti’iking contrast to the almost treeless plain. The soil is gi'ey 
loam as on tin* flats. The s])ecies of Mrhdeucff present are M. leucadendrou . 
M. also})liila and M. ]asi(cu<lra. This association is found along the Nalgi 
frontage betAveen flu‘ ]dain and the si>inifex i>indan. In tlu^ southern section 
of Anna Plains if turns (*astAvai*ds and is lost in the desert. On Wallal isolated 
patches of similar <M)untry are found in a similar situation, but there is no 
distinct sub-zone. 
Apart from the Melaleuca tre(‘s (up to 15 feet high) the vegetation is 
v('ry much the same as on the samphire tlats. HoAvever occasional patches of 
Triodia pungens of the plains form are to be seen, especially Avhere small 
sand drifts have foi'ined under the tv(‘es. The local impression Avas that 
Triafithema turgidifolia had replaced Sporoholu:^ virginiem^ during the graz- 
ing of the yi'ars of occupation. lIoAA’over, since tin; former can Avithstand 
