A thicket of chickweed, Karori. |
Chickweed, Karori. Both leaf surfaces (upper on left), a flower, and a young fruit. |
This is the commonest of the three
introduced chickweeds (the others are S. alsine and S. graminea). There are also five native chickweeds: S.
decipiens, S. elatinoides (probably extinct), S. gracilenta, S. parviflora, and S. roughii.
Stellaria decipiens, Garden Stream, Campbell Island |
S. decipiens is hard to distinguish reliably from S. parviflora, but is often fleshy. It’s confined to the subantarctic islands. This one has no petals, which sometimes happens in S. parviflora too.
Stellaria gracilenta, Canterbury. |
S. gracilenta is a common plant in tussock grasslands in North and
South Islands.
Stellaria parviflora, Mt Herbert, Banks Peninsula. |
S. parviflora is a delicate herb of the forest floor, and common
throughout New Zealand. In the flower above, the petals are the same length as the sepals, although my description in Flora of New Zealand (Webb et al., 1988) says "petals much < sepals or 0".
Stellaria roughii, Cragieburn Range, Canterbury. |
S. roughii is a scree-adapted plant. It has grey fleshy leaves like other unrelated plants in
this harsh habitat.
We don't know yet whether these native Stellarias are all related closely to each other and derived from a single introduction, or whether they represent multiple introductions.
Reference.
Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. 1988. Flora of New Zealand Vol. 4. DSIR, Christchurch.
Reference.
Webb, C.J.; Sykes, W.R.; Garnock-Jones, P.J. 1988. Flora of New Zealand Vol. 4. DSIR, Christchurch.
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