Species

Myosotis laxa subsp. caespitosa

Etymology

Myosotis: mouse-eared
laxa: Slack, loose
caespitosa: From the Latin caespes 'tuft' or 'sod of turf', meaning growing in tufts or patches

Common Name(s)

water forget-me-not

Authority

Mysotis laxa Lehm. subsp. caespitosa (CF Schultz)

Family

Boraginaceae

Brief Description

Low growing herb on wet ground and damp hollows. Leaves are pale green, stems often bend at the base and leaves are willow like. The flowers are small, pale blue with a yellow center.

Flora Category

Vascular - Exotic

NVS Species Code

MYOLSC

The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

Myosotis caespitosa CF Schultz

Distribution

Widespread and very common throughout New Zealand.

Habitat

Margins of ponds and streams and wet hollows, growing submerged in clear fast-flowing streams.

Features

Plants are annual or biennial and 20 to 40 cm tall. Stems are decumbent or ascending. Leaves are narrow, alternate and attached directly to the stem and have pointed or rounded tips with a prominent mid-vein. Leaves usually 30 to 60 mm long, pale green with sparse appressed hairs. Flowers are 2 to 4mm wide, pale blue (with yellow centre). Pedicels at fruiting 2 to 3 times as long as calyx. Nutlets (4) are dark brown.

Similar Taxa

M. scorpioides is similar, but has larger floweres and small calyx lobes.

Flowering

September to May

Flower Colours

Blue,Yellow

Fruiting

Summer to autumn

Year Naturalised

1892

Origin

Temperate Eurasia, East to Himalaya

Reason for Introduction

Ornamental pond and garden plant

Control Techniques

Can be controlled manually, mechanically or herbicidally depending on situation.

Life Cycle and Dispersal

Mainly seed dispersal by water movement and animals contaminated with hooked persistent calyx surrounding seed.

Attribution

Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA).

References and further reading

Johnson PN, Brooke PA (1989).  Wetland plants in New Zealand.   DSIR Field Guide, DSIR Publishing, Wellington. 319pp.

Popay et al (2010).  An illustrated guide to common weeds of New Zealand, third edition.  NZ Plant Protection Society Inc, 416pp.

WSDE (2001).  An aquatic plant identification manual for Washington's freshwater plants.  Washington State Department of Ecology, 195pp.

This page last updated on 30 Jul 2014