Female holly cluster with red drupes |
Wednesday, December 23, 2015
Jolly holly by golly
Tuesday, December 15, 2015
Heed the Seed
Drawing of Tufted Titmouse |
When I read a great blog entry on the Cornell Lab website today, it answered a question I've had for a long time about birds and feeders in the winter upstate. No
matter how many seeds I put in the bird feeder, I find that they are gone in
almost a wink of an eye. I look out and
see the friendly little titmice and chickadees at the feeders non-stop. It turns out that birds, like squirrels and
chipmunks, are caching or storing seeds for the winter when food becomes less
available. So what birds like the
black-capped chickadee, the nutcracker, and the tufted titmouse shown in my
drawing for the Field Guide do is to
gather lots and lots of seed--not only to eat them, but instead mostly to hide
them in all the wonderful nooks and crannies that nature and humans provide—in
knotholes, in the little spaces in bark, in the edges of needle clusters, in
the crotch of branches, and in the crevices and nooks near overlapping
human-made things--shingles, gutters, and overhangs around the house. Titmice usually live their entire lives within
a mile or so of their birth, so they probably know the area around my house
better than I do, and I 'm sure they have their secret spots. Caching is not so easy
for the titmice. They typically do it
one seed at a time, shelling it and hiding the kernel around 150 or so feet
from where they got it. They have to
remember every place they cache their winter reserves too. Animal researchers have found that
chickadees, for example, can remember not only where they have stored their
seeds but also which ones they or other animals have eaten and they remember especially
the caches that contain their favorite food items. Here’s another fascinating find in the study
of chickadees—they actually grow extra neurons in the fall as they get busy
hiding and remembering where they hid their caches. Wouldn’t we all like to be able to do this
when the need arises?
Birds, especially nutcrackers, have been found to establish
thousands of caches containing 100,000 or more seeds in a single year. This behavior has another side effect of
replanting our forests with new trees. When the birds don’t return to eat a
cache, the seeds may start to germinate into a new tree. Here’s something else that you may not
realize. Many birds do not like us to
watch them as they hide their winter cache.
So don’t let them see you as they fly off from your feeder seed in mouth
and heading to their secret cache. They
have learned to be careful of possible cache thieves. So give them their privacy. Everyone needs a private space, even our
favorite feeder visitors.
Saturday, December 5, 2015
Fascicles for a frosty day
Fascicle and White Pine branch |
I love it when two worlds that I study meet over one word. The
word “fascicle” comes from Latin fasciculus
and it means a small bundle or cluster of all different kinds of things. It’s used for small collections of letters,
books, and poems. In biology, fascicle
is used for nerve clusters and muscle clusters, in botany for bundles of
stamens and leaves, and in literature I learned it in terms of Emily Dickinson,
who created bundles of her poems by threading 6 or 7 poems together in little
packets that her friend Mabel Loomis Todd referred to as “fascicles.” And tight bundles of pine leaves or pine
needles are called fascicles, nature’s little winter poems. The number of needles per fascicle distinguishes
one pine from another. Even though it
seems counterintuitive because they don’t look like leaves, pine needles are
leaves or modified leaves in that they perform photosynthesis and manufacture
food, cell respiration, and transpiration (exchanging CO2, oxygen, and water
vapor with the air) for the tree all year long because they are
“evergreen.” The shape of the pine
needles has evolved to help “sift” snow to the ground instead of staying on the
branches and breaking them. The more I
learn about pines, the more amazed I am.
The Eastern
White Pine, Pinus strobus, a
relatively common tree in northeastern forests and a valuable one for lumber, has
five slender flexible needles. As a
child I learned to identify the White Pine from other pines because in its
tight little sheath, it had a needle for each finger, and I could move them
apart and back together to form a hand of sorts. It is a gymnosperm and like many of them it
is evergreen, so we, or at least I, appreciate seeing that deep dark forest
green color among the bare brown branches of the winter woods. Our house upstate is on Tall Pines Road, and
as we drive up the incline from the main road to our house, we pass stands of
100 foot tall white pines, the only green around most of the winter,
and I stare up at the wonder of them.
Tuesday, December 1, 2015
No Bones about Cones
Female Pine Cone Drawing |
I
visited the Hamptons this past Thanksgiving weekend and gathered some pine
cones much as I have been doing since I was very little. I decided to draw one,
and I always read about whatever I am drawing so that I can know it
better. It helps my drawing and my writing. I read that
pine cones have genders, or is it sexes? I knew that pine cones were
the reproductive parts of pine trees (genus Pinus) from my Plant Morphology class at the NYBG, (a class I highly recommend) but I
didn’t think about them as male and female. I wondered whether
they would be easy to tell apart. I wondered which ones I collect and
draw. It turns out the ones I’ve been gathering are the females—ones
that have completed their reproductive cycle. Young female pine
cones are soft, sticky, green, and large; they grow for about two seasons while
their seeds develop. After they are fertilized, they continue to
grow while the seeds mature and gradually they turn brown, woody, and spiky to
protect the seed. Then they open up and let the wind distribute the
seeds; eventually the female pine cones die and fall off the tree for animals
including humans of all ages to gather.
In the pine cone world it seems it is easy to tell the males
from the females by size: the males are smaller, softer, tighter, and more
closed. Most pines are monoecious, having the male and female cones
growing on the same tree. The male pine cones or strobili usually grow toward
the bottom of the tree and the females grow toward the upper
half. Pines are gymnosperms, a word that means “naked seed,” plants
that evolved cones to carry their reproductive structures—ovules for the
females that develop on the scales of the cones rather than in ovaries. The
pollen comes from the male cone, and the wind blows it into the female
cone. Many species of birds and squirrels feed on pine cones, and
just as I found out with acorns, squirrels and birds are not the only ones that
eat pine cones. Humans eat parts of the pine cones—the pine nuts--but we
usually toast them before we eat them. Then there is the
artistic joy of pine cones—they are great to marvel at for their structure and
then to draw.
Subscribe to:
Posts (Atom)