Potamogeton trichoides Cham. & Schltdl.
Conservation status: N, >3
First record: H & J Groves, 1884
29
Nene Washes near Whittlesey, ditch at N end of Paddock 39, cattle grazed with abund. Utricularia, JH Bratton, 12.7.1990, det CD Preston and in CGE as CD Preston 90/249.
Ditch, S of Long Drove, 28–99–, CD Preston 91/157, 17.8.1991, CGE. [not found in CGE.]
36
Appeared in garden pond in 2000 and possibly in 1999, 60 Boxworth Road, Elsworth, Mrs Philippa Harding, det. CD Preston, 31.5.2001.
45
Fen Drain near Cambridge, CE Moss, 1915, Evans,1939: [not given in J.Bot.1938.]
Near Cambridge, CE Moss, 21.6.1915, det Dandy & Taylor, BM.
R. Cam below Jesus Lock, JP Harding, 30.6.1946, det Dandy & Taylor, BM.
Central stream, Coe Fen, 448.573, CD Preston, 5.7.1999, CGE.
Ditch along N side of Garret Hostel Lane, Cambridge, 444.585, CD Preston, 5.7.1999, CGE.
47
Chear Fen, Cottenham, main drain junction, 493.708, GMS Easy, 20.9.1980, PVT.
Chear Fen drain, S of Long Drove, Cottenham, 481.709, CD Preston & NF Stewart, 20.5.1989.
Chear Fen, 48–70–, CD Preston & CFG, 16.9.1995, [R].
Frequent scattered plants, Chear Fen, 490.708, CD Preston & J Fant, 4.6.1996, [R].
Engine Drain, Cottenham, 49–71–, CD Preston & J Fant, 4.6.1996, [R].
Ouse Washes, Sutton, 47J, CJ Cadbury, RSPB Survey, 1992, [R].
Cradge Bank dyke, Sutton Gault area, single site, 42–79–, CJ Cadbury, conf. CD Preston, RSPB Survey, 1992.
Dam Bank Bridge, Haddenham, 423.734, G Crompton & J Bulleid, 21.8.1999, [R].
Adventurer's Drain, 425.734, NP Millar, [R].
48
Hammond's Eau, near Mepal, A Fryer, 5.8.1897, det Dandy & Taylor, CGE. & Dandy & Taylor, J.Bot.1938.
Hammond's Eau, near Mepal, A Fryer, 26.8.1897 & 29.8.1897, det Dandy, CGE, det Dandy & Taylor, 26.8.1897, BM; & Dandy & Taylor, J.Bot.1938.
Drain, Hammond's Eau, EW Hunnybun, 9.9.1909, det Dandy & Taylor, CGE. BM.
Mepal Engine Drain, A Fryer, 29.8.1897, det Dandy & Taylor, BM.
Counter drain at Mepal, 437.815, CJ Cadbury, BSBI Exc. 8.1973.
Sutton & Mepal Drain by Ireton's Way, Mepal, A Fryer, 15.8.1897, AF.ann.
Ouse Washes, Downham, 48Y, 48Z, CJ Cadbury, RSPB Ditch Survey, 1992, [R].
Ouse Washes, Manea, 47–85–, CD Preston & SD Webster, 11.8.1990, [R].
Forty Foot, Manea, 469.858, PH Oswald & BSBI Exc. 31.7.1993, [R].
Main Drain, Haddenham, 482.858, NP Millar, 24.8.1994, [R].
BLOCK FEN
In c.50cms of water with Eleocharis acicularis & Polygonum amphibium, Block Fen, 433.843, BA Adams & CD Preston, 12.7.1988, [R].
Washed up at SW corner of disused flooded sand/gravel pit, Block Fen, Chatteris, 431.840, E of track, NF Stewart & CD Preston, 28.7.1988, CGE.
SW corner of northerly gravel pits immediately E of track, Block Fen, 43–83–, JM Croft & P Hollingsworth, 22.8.1991, [R].
Trout fishing lake, Block Fen, (no grid ref.) JM Croft & P Hollingsworth, 22.8.1991, [R].
WELCHES DAM
Wash ditch by 100ft in Coveney parish opp. Welches Dam, FH Perring, 18.6.1967, det Dandy.
Ditch on wash opp. Welches Dam, FH Perring, 1978; G Crompton, 1979, conf. SM Walters.
Ditch near Welches Dam, 46–84–, MPB Grose & DS Allen, 1978.
Ditch, Ouse Washes, Welches Dam ,c.476.856, with P. pusillus & Zannichellia, CD Preston, 11.8.1990, CGE.
Thinly scattered, in Cradge bank dyke between Common Wash & Norf.border, 48–84–, CJ Cadbury, conf. CD Preston, RSPB Survey 1992.
Ouse Washes, 48S, FH Perring & BSBI exc. 31.7.1993, [R].
Welches Dam, 466.855, CJ Cadbury, BSBI Exc. 8.1973.
Forty Foot Drain, 469.858, PH Oswald & BSBI exc. 31.7.1993, [R].
49
Fenland ditch W of Latches Fen Farm, Wimblington, 427.920, 19.7.1986, CGE.
58
Crooked Drain near Ely, H & J Groves, 1884, det Dandy & Taylor, J.Bot.1938.
Ouse Washes, Downham, 58E, CJ Cadbury, RSPB Ditch Survey, 1992 [R].
Main Drain, Downham, 500.854 & 518.860, NP Millar, 24.8.1994, [R].
59
Cradge Bank dyke, 6 sites between Norfolk border and V.c. 29 border [i.e. V.c. 29 in Norf.] 52–91–, 52–92–, 53–92–, CJ Cadbury, conf. CD Preston, RSPB Survey, 1992.
Ouse Washes, Welney, 53–92–, FH Perring & BSBI exc. 31.7.1993, [R].
