Wednesday 1 February 2012

Poa nemoralis - Wood Meadow-grass

Grass of the Month for February 2012

(See other month's grasses)
Ha -
I bet you did not expect Poa nemoralis to be my next choice for a Poa!

but in winter/early spring it is an excellent choice:-
  • Its new vegetative shoots are growing rapidly at the end of January - (Woodland plants often grow early before the leaves come on the trees)
  • The vegetative blades have strong boat-shaped tips and tramlines (as "good" Poas should) 
  • whereas the blades that will grow on the flowering shoots from April onwards are very flat - almost as flat as Agrostis -and the tramlines and boat shaped tips take a lot of imagination) and the vegetative shoots may have shrivelled by then.


Above is a video of Poa nemoralis in Castleberg Wood (above the Coop in Settle) on Jan 28th - I think the church bell was ringing for a wedding

Jan 28.  2012 South west facing wall at edge of Castleberg Wood -
 See the boat shaped tips

Same plant as above

Beside the path inside the wood.
Last years shoots still have the delicate flowerheads.
 Because it is a wood there was no grazing
and the flower stems have persisted

In winter, as in summer, the flower heads look a bit like
Agrostis flower heads - delicate Christmas tree panicles

This picture needs straightening.
Above the Station water tower is the wood where the pictures above were taken.
This water tower will be on Channel 4 on 16 February

Its still 28 January - but I have walked almost to the station.  
Poa nemoralis grows well on walls - 
maybe its woodland habitat is "chosen" to avoid predation


Taken at the same place near the station
 18 April 2009. It is just coming into flower 

18 April 2009


28 January - Station wall.
You can see how the base of the shoots curve.
 You can also see a node and the stem even here is round. (Poa pratensis would have rhizomes
and some of the shoots may be  more upright from the ground

Same again

This is a Poa pratensis - Its vegetative leaves are
similar - boat shaped with parallel edges and
slightly bluish green - but it has rhizomes - and as seen below has spread between the paving stones of St John's Methodist Church Hall pavement



Poa nemoralis is rare / absent in Western Ireland and scattered in eastern Ireland. It occurs thorugh mainland Britain except the very north west of Scotland http://www.bsbimaps.org.uk/atlas/map_page.php?spid=1504.0


(See other month's grasses)




No comments: