T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Epilobium hirsutum (Great willowherb)

Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Myrtales
Family: Onagraceae
Genus: Epilobium
Species: E. hirsutum
Binomial name: Epilobium hirsutum
Synonyms: Chamaenerion grandiflorum, Chamaenerion hirsutum, Epilobium amplexicaule, Epilobium aquaticum
Common names: Great willowherb, Great hairy willowherb, Hairy willowherb, Codlins and cream, European fireweed, Fiddle grass, Apple-pie, Cheery-pie

Epilobium hirsutum is a flowering plant belonging to the willowherb genus Epilobium in the family Onagraceae. The native range of this species in Eurasia and North Africa and parts of Asia. 
In 2018 Biosecurity New Zealand (MPI) confirmed it has been positively identified at five sites in Canterbury. MPI says initial discoveries occurred in and around the lake at Pegasus township in the Waimakariri District, and near the Kate Valley landfill, approximately 40km north of Lake Pegasus. The finding of this invasive weed is a concern because it has aggressive growth and forms dense stands and it will crowd out native wetland plants. It can also impede water flow in waterways and wetlands.

Epilobium hirsutum is a tall, perennial, semi-aquatic plant, reaching up to 2 metres in height. It typically grows up to 2,500 metres above sea-level in wet or damp habitats without dense tree-cover. Its common habitats include marshland, ditches and the banks of rivers and streams. 
The stems are robust and are covered in soft hairs. 
The hairy leaves are 2–12 cm long and 0.5-3.5 cm wide and they have no stalk. The leaf arrangement is mostly opposite, and the toothed leaves are lanceolate shaped (much longer than wide, and widest below the middle). 
The rose-purple flowers extend from leaf axils near the top of the plant. Flowers are approximately 20 mm across. Each flower has four, green sepals, four notched petals and eight stamens. The stigma is white and has four lobes. 


Seed pods releasing seeds.

Seed pods opening.

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/