Horticulture Heading


Book cover - Common Weeds of New ZealandAn Illustrated Guide to
Common Weeds
of New Zealand


Myriophyllum aquaticum
parrot's feather


Reproduced from
Common Weeds of New Zealand
by Ian Popay, Paul Champion & Trevor James
ISBN 0 473 09760 5
by kind permission of the
New Zealand Plant Protection Society

Publication or other use of images or descriptive text on these pages is unauthorised unless written permission is obtained from the authors and publisher.
Appropriate acknowledgement of the publication Common Weeds of New Zealand must always be given.

Available from Touchwood Books

Myriophyllum aquaticum - parrot's feather

Bottom-rooted, aquatic perennial, with stems emerging above the water surface. Leaves feather-like, finely divided. Forms dense mats floating on the surface, or on damp ground. Occurs in shallow, still or slow-moving freshwater less than 2.5 m deep.

  • Flowers Minute, without petals. Broadly-triangular white sepals 0.5 x 0.3 mm enclose the four-ribbed ovary. Female flowers solitary in the axils of aerial leaves. Male flowers (on different plants from the female flowers) not seen in NZ. Flowers Sep-Feb.
  • Fruit Not set in NZ.
  • Leaves Pale bluish-green, up to 45 mm long by 15 mm wide, in whorls of five or six. Finely-divided into 25-30 awl-shaped leaflets, each up to 7 mm long.
  • Stems Bluish-green, up to 5 mm in diameter. Up to 2 m long, emerging up to 10 cm above the surface. Submerged parts bare, with constricted nodes.
  • Roots Appearing at the lower stem nodes.


Shallow freshwater of peaty or organically rich swamps and drains, lake margins and slow-moving water.


Locally common in scattered NI localities in Auckland, Waikato, Wairarapa and southern Manawatu. Originally from South America.


Listed on the National Pest Plant Accord (see Introduction for details).

Derivation of botanical name

Myriophyllum (Gr.) = many leaves, referring to the finely divided leaves; aquaticum (Lat.) = growing in water.

Get Acrobat Reader

Web-notes: Weed Links

On this site

Reproduced from Common Weeds of New Zealand:

External Links

WeedbustersWeedbusters New Zealand
Weedbusters is a weeds awareness and education programme that aims to protect New Zealand's environment from the increasing weed problem.
A free tool to assist farmers and agricultural professionals in decision-making regarding weed and pest identification, biology, impact and management.
Weed keyNew Zealand Weeds Key
An interactive identification key to the weeds of New Zealand. Developed at Landcare Research.

New Zealand Plant Conservation Network naturalised plants
Search for information on more than 2500 naturalise and weedy plants.
NZ Plant Protection SocietyNew Zealand Plant Protection Society
Their main objective: "To pool and exchange information on the biology of weeds, invertebrate and vertebrate pests, pathogens and beneficial organisms and methods for modifying their effects."
Massey UniversityMassey University Weeds Database
A site providing information about New Zealand weeds and weed control. It has a series of pages showing pictures of New Zealand weeds, notes on identification and control. It also provides information on a university paper entitled Controlling Weeds.

Weeds in Australia
Weeds website of the Australian Government.
Weed Society of Victoria
Promoting wider awareness and interest in weeds and their management. Includes a useful page of links to other weed societies.
Tamar Valley Weeds Strategy
Listing of common and botanical names, images, and information including control methods for weeds found in Tasmania, and also weeds of national significance.

Invasive and Exotic Species of North America
Images and other information from the University of Georgia.

World of Weeds
Weed-related resources including weed science, practical tools, gardening tips about controlling weeds, and environmental news updates.
Invasive Species Specialist Group
"The ISSG aims to reduce threats to natural ecosystems and the native species they contain by increasing awareness of invasive alien species, and of ways to prevent, control or eradicate them."
Site that includes a comprehensive collection of weed images from around the world.

FetchBook.Info Home PageBooks on Weeds from FetchBook.Info

More Plant Profiles

Home | Journal | Newsletter | Conferences
Awards | Join RNZIH | RNZIH Directory | Links

© 2000–2019 Royal New Zealand Institute of Horticulture
Last updated: July 13, 2014