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OBSERVATIONS ON PLANTS in gardens. This attractive flowering shrub would not remain for long unnoticed in the wild, and not be transferred by cottagers to their gardens.

Tulipa silvestris, L. Wild Tulip. Meadows and orchards.

One clump near the River Gipping at Sproughton, where it has been seen for several years. T h e sohtary flower produced most years is too attractive and soon gets picked (F.W.S.). Said to occur near Debenham (Miss B. CopingerHill). This is most likely the Snake's-head Fritillary, the locals all refer to this flower as the " Wild Tulip."

Myrica gale, L. Bog Myrtle, Sweet Gale. Very local. Barnby Broad. Mr. P. J. "Burton informs us that the late Mr. Claude Morley used to visit the bushes at Barnby for a certain i n s e c t / b u t the keeper then burnt them down to keep naturalists away. Lakenheath (B.D.J. and R. G. Rutterford).

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THE marshes of the Minsmere level, with the exception of one field on high ground on which the ruins of the first monastic house at Leiston stands, were all marsh grazings in 1939. 1;he level is divided by a wide ditch, the New Cut. T o the north of this ditch is an internal bank which now forms a central access through the Nature Reserve which has the old Minsmere river as lts southern boundarv. T h e land between the old river and the New Cut forms part of Eastbridge farm and the Lower Abbey farm and it is in this area that I propose to record the p l a n t l i f e which continued to change with altering conditions from 1947 to 1951.

A part of the subject of plant ecology is the study of plants which appear and disappear with changes in conditions brought about by man's intervention or neglect. Whilst there are exceptions to most rules, it is true to say that most plants have a natural set of conditions in which they choose to thrive e.g., the flora of the heath enjoy poor acid conditions and will not naturally grow on heavy clay land of high fertility.

Whilst I did not know Minsmere in 1939, my knowledge from examining marshes on the level which were not so senously affected, leads me to believe that the sward was made u p as follows : bents (Agrostis spp.), crested dog s tail (Cynosurus cristatus), perennial ryegrass (Lohum perenne), fescues (Festuca spp.), wild white clover (Trifolium repens), rush (Juncus spp.) and other typical marsh sward weeds.

67 In June, 1940, the area wasfloodedas a coastal protection measure. The north sluice was opened and salt water flowed in over the Scotts Hall marshes ; at the same time, the sluice door for exit of fresh water from the New Cut was closed. In time, the fresh water and the salt joined levels over the internal bank and the whole area to the north of the New Cut was inundated with salt water, together with a small area to the south-west of the sluice below the New Cut. The sluices were closed and the salt water locked in and the whole area remained under flood until 1945, when the sluices were again allowed to operate normally.

In the early summer of 1947 an attempt was in ade to survey and soil sample this swamp. The ditches were almost completely silted up and therefore the normalflowoff to the sluice was seriously impaired and the level remained under water varying from a few inches to a foot or more according to the season. In March, 1949, a start was made on the excavation of the ditches on an area of 120 acres and by the autumn of 1951, 60 acres had been reclaimed and resown to grass. Theflorawas recorded as conditions changed through drainage, cultivations and fresh water flooding which occurred each winter owing to the inability of the sluice to discharge properly the water of the level. Salt tolerance offloramust be considered in two ways : the saline conditions under which a seed is able to germinate, take root and survive according to its tolerance for such conditions, and the saline conditions under which a growing plant can survive after a salt waterflooding.The Minsmere level is lowest to the east and slightly rises to the west where the depth of salt water was not so great and where the soil texture of the surface six inches was not so heavily laden with silt.

A survey, limited on account offlood,was made early in March, 1947, when the Western group was found to be Agrostis dominant, heavily infested with common rush (Juncus communis) and occasional patches of wood club rush (Scirpus sylvaticus). On marshes 801 and 804, diminutive wild white clover was found in fair quantity. This was the only clover found alive throughout the whole area. At this time of year few weeds were visible : creeping buttercup (Ranunculus repens), marsh ragwort (Senecio palustris), common pearlwort (Sagina apetala), and self-heal (Prunella vulgaris) were found.

In the Central group, there was ample evidence of salt flooding.

No clover or grass was found on 806 and 807. Both were dominant with common reed and wood club rush. Common rush was plentiful, but not in the lowest levels where sea aster (Aster tripolium) was found. Other weeds comprised common nettle (Urtica dioica), spear thistle (Cirsium lanceolatus), creeping thistle (Cirsium repens), marsh ragwort (Senecio palustris), fool's parsley (Aethusa cynapium), willow herb (Epilobium hirsutum), ECOLOGY AT MINSMERE

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celery leaf buttercup (Ranunculus sceleratus), silver weed (Potentilla anserina), and wood club rush (Scirpus sylvaticus).

Marshes 809 and 810 had not suffered to the same extent from theflooding; part of the area is a gorse hill standing about 15 feet above marsh level with a gradual slope towards the old river. There was no white clover, but the lowest parts were dominant with Agrostis. Common rush was plentiful, but not in the lowest levels.

In 812 and 819, some Agrostis was found on higher ground and the remainder of the area was dominant with common reed and wood club rush. All other marshes werefloodedwith at least six inches of water and appeared a sea of reed and rush.

Marestail (Hippuris vulgaris) was found growing in water on mud devoid of other plants near the windpump in 819.

In May, 1949, a month after drainage had commenced, the flora of the six small marshes in the Eastern group comprised small areas of common reed (Phragmites communis), with spike rush (.Eleocharis uniglumis), sea aster {Aster tripolium), and a little club rush (Scirpus sylvaticus). The marshes 820, 821 and 822 were growing a little reed : spike rush was dominant with sea aster and a few plants of wood club rush. Some marestail (Hippuris vulgaris) and fathen (Chenopodium album). On 814, 818 and 819, more than half of the area was covered with common reed and a considerable quantity of wood club rush, spike rush and sea aster.

In the Central group of marshes, 806, 807 and 812 were thickly covered with reed and considerably more wood club rush than in the Eastern group. Spike rush was only found in small quantity in low ground in 812. Sea aster was found in all low places, but in less quantity than was general in the Eastern group.

On slightly higher ground in 809 and 810, creeping thistle (Cirsium arvense), common nettle (Urtica dioica), and common rush (Juncus communis) were found, whilst no reed or wood club rush was found on either marsh. The common rush was not found in any areas where salt contents were high and was confined to soils with a mould layer of at least four inches in depth.

In the Western group of marshes, thefloraindicated that the salt conditions had not been so severe as elsewhere on the level.

Marsh 805 was, however, an exception, and both common reed and wood club rush were found in patches. On the remainder, the general condition was an Agrostis white clover sward, heavily infested with common rush. The clover although diminutive was thriving on slightly higher ground and absent in low places.

O.S. 807. May, 1949. NaCl (Sodium chloride) 0.12% at 24.5.49.

Prior to drainage. A wet marsh with bad waterlogged soil conditions.

Common nettle {Urtica dioica), curled dock (Rumex crispus), chickweed (Stellaria media), silver weed {Potentilla anserina),

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creeping thistle (Cirsium arvense), spear thistle (Cirsium lanceolatum), marsh ragwort (Senecio palustris), fool's parsley (Aethusa cynapium), celerv leaf buttercup (Ranunculus sceleratus), creeping buttercup (Ranunculus repens), willow herb (Epilobium hirsutum), common rush (Juncus communis), bents Agrostis spp.), wood club rush (Scirpus sylvaticus), sea aster (Aster tripolium).

October, 1949. NaCl 0.07% at 8.5.50. found. Teasel (Dipsacus sylvestris).

One new plant was

October, 1950. NaCl 0.09% at 7.11.50. T h e same plants as found in 1949 were present, with the crowfoot buttercup Ranunculus acris) as a newcomer. T h e same were found in June, 1951, with fathen (Chenopodium album) and rough stalk meadow grass (Poa trivialis) as a new introduction.

O.S. 809. May, 1949. NaCl 0.13% at 21.7.49. A fairly dry marsh rising to higher ground. Dominant with bents (Agrostis spp.) with patches of common nettle (Urtica dioica), and creeping thistle (Cirsium arvense) ; common rush (Juncus communis) on high ground, and some creeping buttercup (Ranunculus repens).

October, 1949. NaCl 0.10% at 8.5.50. Creeping thistle (Cirsium arvense), spear thistle (Cirsium lanceolatum), fleabane (Pulicaria dysentericä), greater plantain (Plantago major), ribwort plaintain (Plantago lanceolata), sorrel dock (Rumex acetosa), chickweed (Stellaria media), ragwort (Senecio jacobaea), silver weed (Potentilla anserina), common nettle (Urtica dioica), curled dock (Rumex crispus), *sea aster (Aster tripolium), *spike rush (Eleocharis uniglumis).

October, 1950. NaCl 0.06% at 7.11.50. T h e same plants were found as in 1949. Some greater plantain (Plantago major) and crowfoot buttercup (Ranunculus acris) were recorded, but were probably there in the previous year.

June, 1951. NaCl 0.06% at 20.3.51. Prior to ploughing, the plants already recorded were present and in addition the following were found :—fathen (Chenopodium album), rough stalk meadow grass (Poa trivialis), silver weed (Potentilla anserina).

O.S. 810. May, 1949. NaCl 0.31% at 21.7.49. Prior to drainage, the same plants as recorded for O.S. 809 and with similar dry conditions : bents, creeping thistle, common rush, common nettle, and creeping buttercup.

October, 1949. NaCl 0.06% at 8.5.50. Ground ivy (Nepeta hederaceä), chickweed (Stellaria media), wood club rush (Scirpus sylvaticus), yarrow (Achillea millefolium), common nettle (Urtica dioica), broad leaf dock (Rumex obtusifolius), curled dock (Rumex crispus), creeping buttercup (Ranunculus repens), crowfoot buttercup (Ranunculus acris), snake weed (Polygonum bistorta), silver weed *On lowest ground near the ditch, in higher salt levels.

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(Potentilla anserinä), *wild white clover (Trifolium repens), greater plantain (.Plantago major), sea aster (Aster tripolium), *dwarf eider (.Sambucus ebulus), agrimony (Agrimonia eupatoria), creeping thistle (Cirsium arvense).

October, 1950. NaCl 0.16% at 7.11.50. T h e same plants were found and in addition :—greater plantain (Plantago major), divided sedge (Carex dioica), self-heal (Prunella vulgaris), gout weed (Aegopodium podagraria).

O.S. 812. May, 1949. NaCl 0.39% at 21.7.49 prior to drainage, with salt over 0.3% and limiting flora tolerance.

Incidence.

Wood Club rush (Scirpus sylvaticus) + + Common reed (Phragmites communis) + + Common rush (Juncus communis) + Bents (•Agrostis spp.) + October, 1949. NaCl 0.12% at 8.5.50 after drainage and a fall from 0.39% to 0.12% salt.

Incidence.

Creeping thistle (Cirsium arvense) Star thistle (Centaurea calcitrapa) — Greater plantain (Plantago major) — Curled dock (Rumex crispus) + Sea aster (Aster tripolium) + + Fleabane (Pulicaria dysenterica) + + Creeping buttercup (Ranunculus repens) '+ + Groundsel (Senecio vulgaris) — Black nightshade (Solanum nigrum) — Dwarf eider (Sambucus ebulus) —• Sea club rush (Scirpus maritimus) + and the four plants recorded in May, but in very reduced quantity.

October, 1950. NaCl 0.14% at 7.11.50 after ploughing on 30th June and subsequent discing. Creeping thistle, broadleaved plantain, common rush, fleabane, groundsel, black nightshade, sea aster, common reed and wood club rush. New plants as follows :—curled dock (Rumex crispus), spear thistle (Cirsium lanceolatus), greater plantain (Plantago major), crowfoot buttercup (Ranunculus acris), divided sedge (Carex dioica), red goosefoot (Chenopodium rubrum).

June, 1951. NaCl 0.05% at 20.3.51 after extensive winter flooding on autumn cultivations. Common reed and rush, wood club rush, spear and creeping thistle, crowfoot buttercup, curled dock. New plants as follows :—field sow thistle (Sonchus arvensis), fathen (Chenopodium album), water buttercup (Ranunculus aquatilis), crowfoot buttercup (Ranunculus acris), couch grass (Agropyron * O n higher g r o u n d near a ditch.

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repens), rough stalk meadow grass (Poa trivialis), Yorkshire fog (.Holcus lanatus), marsh foxtail (Alopecurus geniculatus), chickweed (,Stellaria media), annual nettle (Urtica urens). T e n weeks after reseeding to grass :—willow weed (Polygonum persicaria), *golden dock (Rumex maritima).

N.B.—Introduction of wild grasses after fall in sah level from 0.39% in May, 1949, to 0.05% in June, 1951.

At 13th June, 1951, all marshes of the Central group showed a satisfactory " take " of grass and clover seeds, and the swards were comparatively free of weeds which comprised creeping buttercup, spear and creeping thistle, marsh foxtail, and curled dock. A few plants of common reed and wood club rush were present on each marsh.

O.S. 814 AND 818. May, 1949. NaCl 0.54% at 21.5.49. Prior to Start of drainage ; on a common level, in a low area of the marsh and subject to winter flooding.

Incidence.

Spike rush (Eleocharis uniglumis) Common reed (Phragmites communis — Wood club rush (Scirpus sylvaticus) — Sea aster (Aster tripolium) -f November, 1950. NaCl 0.44% (814) and 0.35% (818) at 8.5.50. After cattle grazing from July to October :— common reed (Phragmites communis), creeping thistle (Cirsium arvense), spear thistle (Cirsium lanceolatus), marsh sow thistle (Sonchus palustris), greater plantain (Plantago major), celery leaved buttercup (Ranunculus sceleratus), crowfoot buttercup (Ranunculus acris), water buttercup (Ranunculus aquatilis), f w i l d white clover {Trifolium repens), sea aster (Aster tripolium), silverweed (Potentilla anserinä), common nettle (Urtica dioica), wood club rush (Scirpus sylvaticus), hemlock (Conium maculatum), spike rush (Eleocharis uniglumis), red goosefoot (Chenopodium rubrum), groundsel (Senecio vulgaris), sea spurrey (Spergularia salina).

Atjune, 1951. NaCl 0.13% and 0.08% at 20.3.51. Prior to ploughing. Common reed, spike rush, wood club rush, sea aster, water buttercup, were again found. T h e others of November, 1950, were not found. A few plants of ribwort plantain (Plantago lanceolata) were found, together with marsh foxtail (Alopecurus geniculatus) in considerable quantity, which persisted after cultivations for drilling and displaced perennial ryegrass.

Atjune, 1952. (814) NaCl 0.40% on low levels : (818) NaCl 0.56%. T h e normal grassland and arable weeds were absent, and most of the following found relate to conditions of salinity. *A few plants in a low place.

t A few plants on a ridge.

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T h e high salt levels of Nov., 1950, were reduced by fresh water flooding in the winter (see NaCl at June, 1951) while falsely indicated safety for cultivations. This action and the high summer temperature caused an acute rise in the salt to encourage flora of high salt tolerance. Sea aster (Aster tripolium), marsh foxtail (Alopecurusgeniculatus), common reed (Phragmites communis), common orache (Atriplex patuld), red goosefoot (Chenopodium rubrum), sea club rush (Scirpus maritimus), spike rush (Eleocharis uniglumis), golden dock (Rumex maritima), curled dock (Rumex crispus), sea spurrey (Spergularis salina), water buttercup (Ranunculus aquatilis).

O.S. 822. At March, 1949. NaCl 0 . 5 8 % at 24.5.49. Most of the surface of the marsh was under six inches of water and only one plant, the sea club rush (Scirpus maritimus) was growing in water. (a) Common reed (Phragmites communis) (b) Sea aster (Aster tripolium) (c) Spike rush (Eleocharis uniglumis). (d) Marestail (Hippuris vulgaris) (e) Fathen (Chenopodium album). ( / ) Willow herb (Epilobium hirsutum). ( a ) = i n swamp condition near the ditches : (b) and (c)=all over the marsh in non-flooded areas : (d)=a few plants in wet. m u d near a ditch on higher ground : ( e ) = a few seedlings : and ( / ) = a few plants, both on higher ground.

October, 1950. Conditions fairly similar, but water level reduced to conditions of a wet surface. Marestail and willow herb were not found. Common reed had spread out from ditches.

Atjuly, 1951. NaCl 0.36% at 20.3.51. T h e marsh was still very wet after being flooded over the winter. Common reed had considerably increased and the sea club rush had colomzed all of the previously flooded areas. Other plants f o u n d : — curled dock (Rumex crispus), marsh mallow (Althaea offianalis), marsh sow thistle (Sonchus palustris), fathen (Chenopodium album), hastate orache (Atriplex hastata), bulrush (Scirpus lacustris) eipsywort (Lycopus europaeus), sea aster (Aster tripolium), marestail (Hippuris vulgaris), Canadian fleabane (Erigeron canadensis).

T h i s marsh was never cultivated, but the ditches were excavated in the summer of 1949. Rise and fall of salt levels are due to flooding and temperatures.

P . J . O . TRIST, B . A . ,

M.R.A.C.,

County Agricultural Officer.