Showing posts with label air. Show all posts
Showing posts with label air. Show all posts

Monday, April 2, 2012

Massive Pollen Overload: Hello Spring Allergies

Brace yourself.  These pictures are of terrifying plant structures that cause much anguish to their human victims, and the overall post is frankly somewhat disturbing.  Be brave.  For the first picture, imagine some ominous, slow, suspenseful music, because a threat is just beginning to emerge from its lair.  Yes, the picture below shows flowers from a wind-pollinated tree emerging out of a bud.  The tiny green globs in the picture below will open and shower the world with..........pollen!!! No!!!!  These innocent-looking little guys are going to make you miserable for the next few weeks.


Leaf and flowers emerge from this hornbeam maple tree bud.




"Can those really be flowers?" you ask. "They're so small and boring-looking." Well, not all spring flowers are beautiful and showy.  When flowers are conspicuous, you can rest assured that they are not causing your spring allergies.  Beautiful, sweet-smelling flowers are attempting to attract insect pollinators, and insect-transported pollen sticks to the flower, then to insect legs, and it does not blow in the wind.  Tiny, green, anonymous-looking tree flowers are usually wind-pollinated, which means their pollen is dusty, copious, and perfect for floating along on a breeze to any location, including your sinuses.

"Why do plants make all that pollen?  What's the purpose??!!"  You're asking a lot of questions today. Unfortunately, if you are reading this and sniffling due to a nose full of pollen, you might find my answer to be a little disconcerting.  Pollen is the plant equivalent of sperm.  So, yes, your sinuses are clogged with plant sperm.  Pollen is produced by the male parts of flowers, and it combines with the ovule in the female part of flowers to produce a fertilized cell that will develop into a new offspring plant.  In this picture, you can see the female parts of tiny winter hazel flowers reaching into the air to snag pollen grains to make some new baby hazel seeds that will grow into new hazel trees.


Winter hazel flowers with stigmas reaching out to catch wind-borne pollen.
If you were to look at grains of pollen under the microscope, they wouldn't look much like sperm.  Pollen has varied shapes, depending on the tree.  Here is a book of scanning electron microscope images of different types of pollen - amazing stuff!  My favorite is pine pollen, shaped like Mickey Mouse's head (Google it).

Pollen does a very, very, very strange thing when it fertilizes plant ovules.  When pollen lands on a female flower structure, it divides into three sperm cells, with actual flagellae.  The sperm swim down a channel in the female structure of the flower.  One sperm fertilizes the ovule, as we would expect based on what we learned about human anatomy in 7th grade.  The other two sperms combine with another cell near the ovule to make a substance called endosperm.  The endosperm is genetically the combination of two parents, but it is not really an offspring.  Endosperm is the structure inside the seed that stores food for the new growing plant.  For example, in a corn seed the endosperm is the starch in the corn kernel (yes, popcorn is exploded endosperm, and the little nubs in popcorn are toasted corn embryos....mmmmm!). Now you know why I put three "verys" in the first sentence of this paragraph.


New leaves and flowers hanging in clusters called catkins on a red oak tree.

Oak trees (pictures above and below) are my favorite trees, so don't think I'm picking on them.  They are pretty bad at making giant clouds of pollen.  Pines are even more intense.  There are a few days in spring in Georgia that you really don't want to be outside because the pine trees seem to spew pollen like snow-making machines spew snow.  If you catch a tree as it's releasing pollen and shake one of it's branches, you can make a nice, yellow cloud in the air.

When pollen lands inside your nose, the membranes in your nose recognize it as a foreign object to be removed.  Your body leaps into action with sneezes, mucus production, and swelling (which can cause headaches) in order to get rid of the pollen.  This immune response can make you tired and uncomfortable.  Fortunately trees only make pollen for a short period of time.  The benefits of having lots of trees near you (shade, habitat, aesthetics, food, property values, reduced heat bills, etc.) vastly outweigh the annoyance of allergies.  If your spring allergies are really bad, stay inside and be sure to wash your hair and clothes after you go outside to keep the pollen away from your nose.  And just wait around a few days for a spring rain shower, and the pollen will be gone.

New leaves and catkins on a white oak.





Saturday, June 4, 2011

Sound Exchange

The sounds changed even in the car on my way out of the city, well, I changed the sound anyway. For some reason, NPR's reports on the daily movements of Al Quaeda grated more than usual, and I switched to music. My poor little car radio has been waiting for years to play something other than news.

As I neared the little farm where I'll be working this summer, I opened the windows and let the country smells and sounds in. The air shifted as I got off the highway. Southern country air is thick, dense and sweet in the summer. When you step out of air conditioning, it feels a little syrupy for the first few breaths until your lungs relax. Southern city air is also thick and dense in summer, but it has a sticky sour quality to it, perhaps from the additional particulates or ozone.

It's not technically summer yet, but you can be fooled into thinking it's summer in the daytime heat. At night, the air is still cool and dry - a sure sign of spring.

The farm itself turned out to be everything I had imagined a picturesque organic farm to be. It has gorgeous rows of greens and flowers, edges of grasses and rural weeds, a sturdy old barn leftover from the last farm, two hoop houses and the owners' house complete with skylights.

I quickly fell into the old familiar rhythms of farm work. In college, I worked on the state of Florida's research farm assisting a plant geneticist. The job was long days of transplanting, mixing soil, watering, fertilizing and spraying pesticides. There is a kind of zone that the body goes into when actively working all day in the heat. It is almost surprising to be quick and strong in intense heat. It was satisfying to revisit those sensations from a younger age with the perspective I have now.

Since I enjoy the work and the atmosphere, the stretching of time that happens with a pleasing repetitive task gives way to thoughts. It was my first day, so there was a lot of conversation with the farm owner and the other worker. I hope that will continue, but I also know we'll all fade into long stretches of nothing but farm sounds and our own thoughts. The contrast with my old job in these aspects is almost comical. The pace of high school teaching is like a car race - constant, hectic, loud and inconsiderate. I enjoyed the excitement of quick decisions and rapid-fire intellectual problem solving, but there was never time to reflect or converse at length with colleagues, and the repetitive work required all one's attention, or one would be embarrassedly fixing idiotic grading errors the students noticed. Time passes not in minutes but in weeks at school. Each glance at the calendar requires the crossing-out of a shocking number of boxes.

I wasn't sure I'd still be up to the task of laboring all day in the sun, but I made it through easily. Next time, I'll bring a little more water, as water becomes much more appealing than even my favorite dessert when I'm sweating like that. I'll also bring my own big straw hat and a handkerchief - two essential items of comfort. One provides an umbrella of shade, and the other provides passing moments of dry skin. Sweat cools best when there is just a little of it on the skin, but for some reason, my sweat glands seems to increase their output in a linear fashion with the temperature, so I need to mop it off to have a few moments of cooling as the next batch of sweat starts to pour out.

As I drove home, I was thankful to have completed my first First of the next phase of life. Quitting my teaching job required giving notice in March, telling students and colleagues in April, and doing things for the last time since I knew I would be leaving. It's been months of sad goodbyes and well-wishing. I am satisfied with the work I did, and I hate to lose that truly wonderful community. Since it had to happen, I must admit I've been a little antsy to get on with it. Yesterday, I finally cleared out my classroom and surrendered my keys to the school, and from now on, my days are about building my next life. I know I'll find ways to weave threads of my teaching life into my future life. My nomadic childhood taught me that old friendships must be maintained intentionally, so I'll put in the effort to make it happen. But now, I'm doing everything for the first time again - first day on the new job, first blog post, first time designing my future with intention.