Sunday, 22 April 2012

Poppy Day

ANZAC Day is probably New Zealand’s most special day.  Like Remembrance Day in the UK, it's the day we remember the sacrifices our soldiers made in two world wars.  Like Remembrance Day, the symbol of ANZAC Day is the poppy.  Not only that, but it's often said that the battle of Gallipoli, which it originally commemorated, was when New Zealand grew up, whatever that means.
Wellington's superb art deco war memorial in Buckle Street.  The tomb of an unknown soldier is here.
 In the past, particularly during the Vietnam War, ANZAC Day was sometimes controversial.  This year the poppies themselves have been a bit controversial, because instead of being made in the sheltered workshops in Christchurch, the poppies on sale are mostly made in China.  Some people have suggested we should make our own, but give a donation to the Returned and ServicesAssociation anyway.
So what are they like, these ANZAC Day poppies?  Of course they're symbolic, not intended to be botanically correct, but how well do they do from a botanist's point of view?
The first ANZAC Day poppies I remember were from the late 50s or early 60s.  There were two kinds.  Either you could get a nice fabric 3D poppy for your donation, or you could get a slip of paper with a picture of a poppy printed on it.  The 3D poppies were interesting, because, although they were the right shade of red, they didn't look a lot like a real poppy.  Rather, they were more like a Californian poppy (Eschscholzia californica) in shape, with a conical corolla.  
Californian poppy, Eschscholzia californica, Central Otago, New Zealand.
Later (maybe in the 1980s or 90s) they changed the design, to this:
In many ways, this is a more realistic poppy.  It has opposite petals and a dark black spot in the centre of the flower.  But, when you look at a real poppy it's not really like that.
Papaver rhoeas, Sete, southern France.
First, there are four petals, not two. Four is an unusual number of petals in flowers.  Monocots usually have three or six, and Eudicots mostly five.  Some Lamiales have four, mostly it seems because two of the five petals have fused together, as in Veronica.  The evidence for that interpretation is in the two sets of vascular bundles that supply the enlarged posterior petal and the quite common occurrence of a divided petal (strictly speaking, in families that have the petals united at their bases into a tube, each is called a corolla lobe rather than a petal). A few families are characterized by truly having four separate petals, e.g., Onagraceae (evening primroses, Fuchsia, etc) and Brassicaceae (the mustard family).  And of course the poppies and their relatives mostly have four petals. 
Long-headed poppy, Papaver dubium, Roca Grosso, Catalonia.
 Poppy flowers are interpreted as having two whorls of two petals, rather than one whorl of four like Brassicaceae.  This is because (1) the outer pair overlaps the inner pair, (2) the calyx has just two opposite sepals and development of calyx and corolla are often related, and (3) in a few poppies, like P. bracteatum, there has been a duplication of a whorl to give 6, not 8, petals.  [Note added later: Point 3 isn't well argued, because those poppies have two whorls of three petals, not three whorls of two.  So rather than have a whorl duplicated, each of the two whorls has increased the number of its parts from 2 to 3.  However, if it had been a single whorl of four petals, such an increase would give five (i.e., 4+1) rather than 6 (i.e., 2x(2+1))].  So the ANZAC poppy is botanically correct in having a pair of opposite petals, but wrong to have just one pair. 
Sepals fall early in poppies, as the flower opens (in Californian poppies they’re joined as a cap that pops off the opening flower), so you wouldn't put sepals on an ANZAC poppy.
The black spot in a poppy isn’t in the centre of the flower, but there’s one at the base of each petal.  The spot is a variable feature.  Sometimes, especially in cultivated Shirley poppies, it’s absent, or even white.  The makers of ANZAC poppies have used the black dot as a constructed feature that holds the corolla onto the pedicel (stalk) of the flower, but they would have done better by making it green to represent the ovary and stigma.  In the true poppies (Papaver), the stigma is a large flat or conical disk on top of the ovary, and the receptive surfaces (where the pollen adheres) radiate out like the spokes of a wheel. 
In flowers, the stamens are found between the petals and the ovaries, and in poppies there are a large number of them.  The stamen filaments are black, so they do add to the central black area.  Multiple stamens are hard to represent in a fake flower that has to be cheap, but a tuft of dark plastic strands would do the job.
Poppy flowers are fragile, and the petals and stamens soon fall.  They can be made to last a day or two in a vase if you pick them as buds before the stalk straightens (below on the left hand side) and singe the cut ends of the stalks (the milky latex sizzles and maybe it seals the vascular bundle although I don’t know why that would make the poppy last longer).  Later, the ovary swells and becomes the seed capsule.  Tiny pores open in a ring below the lobes of the stigma, and the seeds are shaken out through these.
Corn poppy, Papaver rhoeas, Kaikoura, New Zealand.
The poppy day poppy is modeled on the corn poppy, Papaver rhoeas, but other poppies are very similar.  In New Zealand the long-headed poppy, P. dubium, is quite common, along with a couple of other similar red-flowered species.  Iceland poppies have a range of flower colours.  These are all annual poppies, but there are perennials too, like the oriental poppies P. orientale and P. bracteatum and the orange-flowered P. atlanticum.
Papaver atlanticum, Dunedin Botanic Gardens, New Zealand.
Another poppy has a longer association with warfare.  The opium poppy (Papaver somniferum) is the only natural source of morphine, used for thousands of years as a pain killer.  All poppies have related alkaloid compounds.  Most of these are very unpleasant and dangerous poisons, but thebaine and codeine are used in medicine.
Opium poppies, Wiltshire, England.

No comments:

Post a Comment