Pine tassels. © Beatriz Moisset |
Pine cones. © Beatriz Moisset |
Maine’s state flower is rather
unusual because it is not a flower in the real sense. It is the white pine’s (Pinus
strobus) tassel and cone. These are not flowers but serve the same function:
the tassels produce pollen that has to arrive at the small, immature cones to
produce seeds. Only then the cones can grow and reach maturity. Maine residents must be
mighty proud of their pines and for very good reasons. It is a handsome tree of
great value, and the tassels and cones, although not as colorful as most true
flowers, are quite handsome. I am delighted at this peculiar choice because it serves to illustrate a significant point of pollination.
Long
before there were any animal pollinators, only the wind performed this
function. Wind pollinated plants have to produce vast quantities of pollen so
that just a few grains can arrive to their destination; the immense majority
never even come near the female cones and simply goes to waste. Pines,
firs, spruce, and other conifers belong to an ancient lineage that appeared long
before pollinators entered the scene. Thus they were and still are pollinated
by the wind. Despite its inefficiency, this method works well enough when many
plants of the same species grow relatively close to each other. This is why
conifer forests are composed of only a small number of species. This is also
why corn, another wind pollinated plant, needs at least several rows of plants
to produce seeds.
Pollen dispersal by wind. © Beatriz Moisset |
Getting
back to the pine, both the tassel and the cone are well-adapted to their
functions, increasing the chances that wind-carried pollen finds its
destination. The tassels are placed higher on the tree. The cones are
aerodynamically shaped to create small air whirlpools that direct the pollen
grains toward the seeds. For millions of years, the land was dominated by these
plants, along with even older ones, the seedless ones that reproduce by spores.
The more ancient dinosaurs never saw a flower, nor did they care. The flower
revolution was yet to come, and once started it would take the land by storm
and spread to distant corners. Nowadays, wind pollinated conifers are more
common than flowering plants only in harsh and cold environments near polar
regions. Most plants everywhere else produce flowers.
The
great advantage of flowers and of animal pollinated plants is that pollinators
are more efficient than wind alone in transporting pollen to the intended
target, thus even if individual plants are far apart, they still succeed at being
pollinated. In fact, forests of tropical regions are made largely of blooming
trees with so many different species packed in the same space that a pollinator
has to travel some distance between members of the same species. So pollinators
contribute to biodiversity, which in turn contributes to a more efficient way
of using all available ecological resources.
Now I
can get on with the story of pollinators of state flowers.
Also see: Pollinators of Official State Flowers
References
Maine: White pine tassel and cone
List of articles
Beginners Guide to Pollinators and Other Flower Visitors
© Beatriz Moisset. 2015
Also see: Pollinators of Official State Flowers
References
Maine: White pine tassel and cone
List of articles
Beginners Guide to Pollinators and Other Flower Visitors
© Beatriz Moisset. 2015
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