Page 1

37

BLYTHBURGH MARSHES

and making better growth alongside water Channels. T h e dominant plant of the whole area was Suaeda maritima. Atriplex hastata has established itself in the dry areas but the plants were not the normal size and it will be seen that as the salt decreases, both the size of the plants and their numbers relative to other salt tolerant flora will increase. There is no Atriplex littoralis established on the marsh, but it can be found on the wall. Salicornia stricta is not yet abundant: most is found in damp low places with a few plants of S. ramosissima. Halimione portulacoides is found, but so far it is a rare find. Equally there are only isolated plants of Glaux maritima. In wet areas and alongside running water, there is a small colonization of Phragmites communis and Juncus gerardi, which will no doubt spread considerably next year. In similar conditions are two interesting finds. A single plant of Polygonum aviculare which I have previously noted has a salt tolerance up to 0.3% NaCl, appears to have relations with hardier constitutions. T w o strong plants of Ranunculus sceleratus Standing erect 2\ ft. high were flourishing in the high salt content. P. J.

O.

TRIST.

SEA CLUB RUSH. Scirpus maritimus L. : F O U N D by Mr. T . B . Ward of the Essex Field Club on the joint excursion to the Stour Valley, by a pond in the Gravel Pit at Thorrington Street. " This is," he said, " the furthest inland that I have observed it." He had previously found this plant near a pond at the highest point in Essex at Danbury 350 ft. above sea level. T h e normal habitat of Scirpus maritimus is near the coastline in wet conditions, either fresh or salt, but it more freely colonizes in salt conditions. Of the salt tolerant flora, the majority have a ränge of salinity which is tolerated. This rush is an exception. At Minsmere, in 1949, it was growing in salt conditions which ranged from 0.05% to 0.9%* : but it had colonized the bare mud of the marsh (where wartime seawater flooding had killed the sward) more freely where the salt exceeded 0.4%. On the other hand, it finds a safer habitat when establishing itself outside the defences of a tidal river and is generally found behind the mark of high spring tides, on a line with Juncus gerardi. When found in marsh ditches near a river wall, it is frequently an indication of a seepage of sea water through the base of the wall into the ditch : and if in Company with Spergularia salina and Salicornia spp. there is no further doubt of the presence of salt. P . J. O .

* g salt (NaCl) per 100 g dry matter.

TRIST.

Sea Club Rush  

Ward, T. B. & Trist, P. J. O.

Read more
Read more
Similar to
Popular now
Just for you