Lythrum hyssopifolia
Common names
hyssop loosestrife
Biostatus
Exotic
Category
Vascular
Structural class
Herbs - Dicotyledons other than Composites
Simplified description
Low growing, many branched herb with narrow leaves, either in pairs or individual up to 2.5 cm long, and small (4 mm across) pink flowers produced directly from the stem next to the upper leaves.
Flower colours
Red/Pink
Detailed description
Glabrous annual with diffuse or dense habit; stems to c. 40 cm tall, ± quadrangular, often pinkish, sometimes producing roots towards the base. Lvs sessile or subsessile, (6)-8-25 × (1.5)-2-8 mm, usually linear or narrow-linear, sometimes linear-oblong on lower part of main stem and on young plants, entire; base rounded to subcordate; apex acute or obtuse. Fls solitary in lf axils, monomorphic. Pedicels < 1.5 mm long; bracteoles > pedicels. Calyx 3-5.5 mm long; tube narrow-obconic and tapering gradually to narrow base, ribbed; lobes 1-1.5 mm long, narrow-triangular to linear-subulate; epicalyx segments 0.5-0.8 mm long, broad-triangular. Petals 6, 2.5-4 mm long, pink, crumpled; claw short; limb elliptic-obovate. Stamens (3)-4-7-(10), included; filaments generally of different lengths. Style 1-2.5 mm long. Capsule 4-6 mm long, cylindric, included in calyx tube. Seed 0.7-1 mm long, ovoid, slightly asymmetric.
Similar taxa
Similar to rose loosestrife (Lythrum junceum), but all parts of that plant are larger.
Distribution
Common throughout both islands as far south as Otago
Habitat
Wet disturbed places such as roadside gravel and exposed margins of water bodies.
Conservation status
Not applicable
Detailed taxonomy
Family
Ecology
Flowering
Summer
Fruiting
Autumn
Year naturalised
1855
Origin
Europe, western Asia and North Africa
Reason for introduction
Unknown, seed or soil contaminant
Control techniques
Not controlled in New Zealand.
Life cycle and dispersal
Seed dispersed by water, animals or contaminated machinery.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Other information
NVS code
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.
LYTHYS
Referencing and citations
References and further reading
Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. (1988). Flora of New Zealand Volume 4: Naturalised pteridophytes, gymnosperms, dicotyledons. Botany Division, DSIR, Christchurch.
Popay et al (2010). An illustrated guide to common weeds of New Zealand, third edition. NZ Plant Protection Society Inc, 416pp.
Johnson PN, Brooke PA (1989). Wetland plants in New Zealand. DSIR Field Guide, DSIR Publishing, Wellington. 319pp.
Clapham, A.R.; Tutin, T.G.; Warburg, E.F. (1962). Flora of the British Isles. Cambridge University Press, Second Edition. 1269pp.
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Features description from Webb et al. (1988).
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.