Araceae . . . . . . Arum family

Also includes former Lemnaceae

Araceae - Choose: Using (a) Flowers . . . or . . . (b) Leaves . . . or . . . (b) Floating plants


Flowers:

Acorus
Arum
Zantedeschia
Lysichiton

Leaves:

Acorus
Arum
Zantedeschia
Lysichiton


Arum
Asarum

Small floating plants:

Wolffia
Lemna
Lemna
Spirodela

Acorus . . . . . Sweet-flag


Acorus calamus . . . Sweet-flag

A plant of pond edges:

Arum . . . . . Arum


Arum italicum . . . . Italian Lords-and-Ladies

Similar to A. maculatum though A. italicum usually has pale leaf midrib and top of spadix yellow not purple; commonest in CI and near S coast and SE Ire, becoming more scattered in N En

Arum italicum subsp. italicum . . . . Italian Lords-and-Ladies (subsp. italicum)

Characteristic white veins and top of spadix yellow; commonest in CI and SW but can persist further N as garden thow-out

Arum maculatum . . . . . Lords-and-Ladies

Has purple spadix and no pale veins in leaf which often has a dark spot; the commoner sp. occurring everywhere in BI exc. NW Sc

Lysichiton . . . Skunk-cabbage


Lysichiton americanus . . . . American Skunk-cabbage

Garden escape growing particularly in damp areas

Zantedeschia . . . Arum Lily


Zantedeschia aethiopicus . . . Arum Lily

Garden escape growing particularly in damp areas

Arisarum . . . Friar's cowl


Arisarum vulgare . . . Friar's-cowl

A similar Mediterranean plant is rarely encountered as a garden escape

Former Lemnaceae . . . . Duckweeds

Former Lemnaceae:
Wolffia
Lemna
Lemna
Spirodela
No roots
1-root
1-root
3+-roots

Lemna . . . . . Duckweed

Lemna have clear single roots attached to each frond

Lemna minor . . . . . Common Duckweed

Common throughout BI on ponds; fronds flat on both surfaces with 3 faint ridges (veins) on u. surface

Lemna minuta . . . . . Least Duckweed

Fronds <3mm long; frequent in still water in En, Wa, Ire; local in Sc

Lemna trisulca . . . . . Ivy-leaved Duckweed

Frequent in still to flowing water in lowlands esp. in S Br and in C Sc; largely submerged

There are several other spp.: a frequent sp. is L. gibba (fat duckweed) which has +/- hemispherical "leaves"

Spirodela . . . . . Greater Duckweed


Spirodela polyrhiza . . . . . Greater Duckweed

Larger, Fronds c.10 mm, >5 roots on each frond, rather local in Ire and mostly in S Br

Wolffia . . . . . Rootless Duckweed


Wolffia arrhiza . . . . . Rootless Duckweed

Rootless duckweed is tiny (c.1 mm), has no roots and is local in SE En and around Severn estuary