|Female holly cluster with red drupes|
Wednesday, December 23, 2015
Tuesday, December 15, 2015
|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
|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
|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.