Archive for April, 2010
Friday, April 30th, 2010
¬†¬†¬†¬† Discussing trees with my Master Naturalist class the other night,¬†it became¬†clear to me that¬†I’ve forgotten much of what I learned long ago about plant reproduction.¬† And now that I am studying trees,¬†I¬†realize that tree¬†reproduction is more complex than I ever imagined!¬†
¬†¬†¬†¬† Let’s see. . . . .I remember that trees reproduce¬†sexually, although I now¬†know¬†that some trees,¬†like the paw paw, can also¬†produce asexually, or ‘clonally’ by spreading runners under the ground¬†when the right pollinating animal no longer lives in the area.¬†
¬†¬†¬†¬† But back to the¬†reproductive life of trees:¬† They reproduce when the¬†pollen–the male part of the process–fertilizes the egg–the female.¬†¬†From fertilized¬†eggs, then, come seeds, which are dispersed.¬† Some of the seeds take¬†root, and the next generation is launched.¬† That’s the three-sentence summary.¬†¬†¬†
¬†¬†¬†¬† As with herbaceous plants, trees have evolved an incredible array of methods for getting the pollen and the egg together and for dispersing the¬†seeds that result from their ‘parents’ union.’¬†¬† In¬†some species, for example, the pollen from male flowers, catkins, or cones,¬†is blown by the wind to the female flowers, on another tree or on the same tree.¬† With other species, it is insects¬†who transfer the pollen to the female flowers.¬†¬†
¬†¬†¬†¬† Once pollination has occurred, the resulting seeds need to get into a good spot of earth to germinate and grow new trees.¬† As with pollination, nature has¬†evolved¬†ingenious¬†ways to get the job done.¬† Wind, water, and animals are all ‘used’ by trees to move their seeds away, to another spot where they might take root and grow.¬† Interestingly, the trees that depend mainly on wind¬†dispersal¬†produce volumes more seeds,¬†since the odds that any one seed will be blown to a¬†favorable spot and take root are very slim.¬† Trees that produce seeds eaten by animals, however, like the oak’s acorns, are far fewer.¬† Such seeds have a much better chance of being carried to–and ‘deposited’ in–a favorable location where they can germinate.¬† So not nearly as many of these kinds of seeds are needed to perpetuate the species.¬†
¬†¬†¬†¬† Although quite incredible, this all sounds straightforward enough.¬† But I am still puzzled.¬† When I walked down into the woods yesterday morning, I looked at the catkins of tiny flowers hanging from¬†striped maples.¬† Some of the little trees had them, and some appeared to have no flowers at all.¬† So, how, I wondered, would pollination take place when some of the trees lacked an ‘organ’ for bringing pollen and egg together?
¬†¬†¬†¬† Once back home, I did a little research and found that¬†striped maple reproduction is more complicated than I would have guessed.¬† Here is a quote from an article by Boston University professor Richard Primack,¬†intriguingly¬†titled The Sex Life of the Red Maple.¬† “Individuals of this [striped maple] species often produce clumps of woody shoots that produce male flowers for a few years, followed by female flowers and fruit production for a few years, until the shoot dies.¬† The rootstalk sometimes produces many shoots, each one going through this cycle, keeping the plant alive even though individual shoots die.”
¬†¬†¬†¬† As you can imagine¬†from the title of Primack’s article, the red maple’s reproduction is even more complex than that of the striped maple!¬† In fact, right now as I look out admiringly¬† at a red maple, with its already well-developed winged seeds, or fruit, I contemplate the fact that it is a female tree, at least for now.¬†¬†¬†¬†
¬†¬†¬†¬† You see, according to Primack,¬†some¬†red maples produce female flowers, others produce male flowers, and some even produce both kinds!¬†¬†But red maple reproduction is¬†more complicated still.
¬†¬†¬†¬† Primack writes that botanists had been puzzled to find male red maples producing fruit!¬† He decided¬†to study red maples¬†to find out what was going on.¬† Starting in 1979, he monitored a group of 79 red maples for many years.¬†¬†He concluded that 53 of them were male, and always produced male flowers.¬† Six of the trees were mostly male. That is, they¬†produced mainly male flowers, but in some years also produced a few female flowers.¬† Twelve more trees were constant females, producing only female flowers every year.¬† And six¬†more were mostly female, also producing a few male flowers in some years.¬† And then there were two trees that produced¬†’perfect’ flowers, botanese for¬†flowers¬†that have both male and female parts and thus self-pollinate.¬†¬†
¬†¬†¬†¬† Primack’s¬†findings are fascinating.¬† But I am still left with questions.¬†¬†Is his sample of red maples truly representative of the entire¬†species?¬† Are the overwhelming majority of red maples¬†male?¬†¬†I also wonder how red maples are pollinated.¬† Wind?¬† Insects?¬† I tried to find the answer to that question, but it seems¬†open to debate.¬† Some say wind only;¬† others¬†maintain that bees love the red maple flowers and thus must be transferring pollen.
¬†¬†¬†¬† Nature certainly has evolved some ingenious¬†ways to perpetuate life!–April¬†Moore¬†¬†¬†¬†¬†
red maple leaves and seeds outside our window
Tuesday, April 27th, 2010
¬†¬†¬†¬† For the first time in more than a century, a California condor chick has hatched inside Pinnacles National Monument, the federal wildlife reserve in California that was once the species’ domain.¬† The young condor chick brings the total number of California condors in the world¬†to 350.
¬†¬†¬†¬† Biologists and others have been celebrating the birth.¬† After all, this bird–the largest North American land bird–was at the brink of extinction less than 30 years ago.¬† In 1982,¬†only 22 of the birds were left in the world, thanks to habitat loss, poaching, and lead poisoning.¬† Those¬†birds were then¬†placed in a captive breeding program at the San Diego Wild Animal Park and the Los Angeles Zoo.¬†
¬†¬†¬†¬† By 1991, the condors’¬†numbers had increased enough that biologists could begin reintroducing the birds into the wild, to their native California and the Southwest.¬† Now, about 180 of the 350 California condors live free in the¬†Grand Canyon area, Zion National Park in Utah, and in the coastal mountains of California and northern Baja California.¬†¬†
¬†¬†¬†¬† The newest condor chick is being raised by a female who was released into the wild in 2004¬†at Pinnacles and by a male released that same year on the California coast.¬† The couple had produced an egg that proved not viable,¬†so¬†biologists replaced the egg in the bird’s nest with a fertile condor egg.¬†¬†¬†
¬†¬†¬†¬† The California condor is an impressive bird.¬† It is a¬†black vulture with a largely bald head.¬† The skin color of the bird’s¬†head ranges from yellowish to bright red, depending on the bird’s mood!¬† The wingspan of the California condor is wider than that of any¬†North American bird, and the condor is¬†one of the longest-living birds in the world.¬† A California condor can live for up to 50 years.¬† A scavenger, the condor¬†eats large amounts of¬†carrion.
¬†¬†¬†¬†¬†I am thankful to the scientists and others who worked¬†with care and wisdom¬†over the¬†years to prevent¬†the complete extinction that would have taken place without their committed efforts.–April Moore
photo by Michael Quinn
Friday, April 23rd, 2010
¬†¬†¬†¬† As you likely know if you have been reading The Earth Connection for a time, I am an ardent¬†lover of trees.¬† They awe me, delight me, comfort me, and engage me.¬† I thank my friend Caroline for bringing these amazing photos to my attention.¬† I hope you will enjoy them too.¬† Just click on the link below.–April Moore
Tuesday, April 20th, 2010
¬†¬†¬†¬† Imagine this scene.
¬†¬†¬†¬† It is a moonlit night in the Hawaiian Islands.¬† A¬†bobtail squid is gliding¬†along through shallow waters.¬† But despite the moonlight, the squid¬†casts no shadow on the seafloor as it swims.¬† Why not?
¬†¬†¬†¬† Since a moving shadow in the moonlight could alert the squid’s predators to the animal’s presence, this creature has evolved an incredible mechanism to avoid casting a shadow.¬† When darkness alone won’t serve to hide the squid, it produces its own light, which shines downward onto the seafloor.¬† The squid can even modulate the brightness of the light it generates, so that it¬†matches the intensity of the surrounding moonlight on the seafloor!
¬†¬†¬†¬† How is the squid able to¬†protect itself in this amazing way?
¬†¬†¬†¬† Scientists have discovered the squid’s secret.¬† The bobtail squid has a bioluminescent organ on its underside.¬† Inside this organ is a population of bacteria that glow in response to changes in oxygen concentrations in the squid.¬† Inside cells around the bioluminescent organ, as well as in cells in the skin,¬†ink sac, and around the eyes, are reflective, iridescent structures, called platelets,¬†that reflect the bacterial light.¬†
¬†¬†¬†¬† While many aquatic creatures can reflect light, they cannot modulate their light to match surrounding light, as the bobtail squid can.¬† The platelets of these other light-reflecting animals¬†have a rigid structure that does not allow for changes in reflectivity.¬† The squid’s platelets, however, are made of flexible protein structures that allow the animal to¬†alter its reflectivity.¬†¬† Hence, the bobtail squid’s ability to match its own downard shining light with the¬†intensity of the moonlight shining on the seafloor.
¬†¬†¬†¬† Amazing,¬†huh?–¬†April Moore
Hawaiian bobtail squid
Monday, April 19th, 2010
¬†¬†¬†¬† Great news!¬†
¬†¬†¬†¬† Trees, those¬†marvelous beings¬†who absorb carbon from the air, who provide¬†habitat for numberless species, who refresh us with their shade and beauty, are¬†doing well in an important way.¬†¬†¬†¬†
¬†¬†¬†¬† According to a new United Nations study, the worldwide rate of deforestation has declined for the very first time.¬† The years 2000-2009 saw a significant drop in deforestation¬†from the previous decade.¬† Deforestation during the 1990s averaged more than 20 million acres of forested land lost per year, compared to 12.8 million forested acres lost annually since 2000.¬†¬†¬†
¬†¬†¬†¬† The reason for this first-ever decline in the¬†deforestation rate, say the authors of the¬†study, is the growth in tree planting programs.¬† In the United States, China, Brazil, Vietnam, India, Indonesia, and in many other countries around the world,¬†tree planting programs have increased forest coverage by millions of acres per year, according to the UN report.¬†
¬†¬†¬†¬† A lower deforestation rate, combined with newly planted forests, “have helped bring down the rate of carbon emissions,” said Mette Loyche Wilkie of the UN Food and Agriculture Organization.
¬†¬†¬†¬† Despite this excellent news, researchers are concerned that deforestation rates will again start to climb.¬† Scientists point out that global warming is devastating millions of acres of trees, as¬†warmer temperatures¬†lead to more insects and more damage to trees.¬† Another concern is that some replanting programs are scheduled to end in the next few years.¬†
¬†¬†¬†¬† Yet another worry is agriculture.¬† UN scientists are studying the impact that clearing millions of acres of forest for crops and livestock¬†has on deforestation.
¬†¬†¬†¬† I raise another concern.¬† I have read that some tree planting programs are not well-planned, with biodiversity and the complexity of a healthy forest in mind.¬† Planting the wrong¬†tree species or too few species¬†of trees may¬†make for a much less healthy forest system than the original forest cover.
¬†¬†¬†¬† Still, the fact that forest cover on the planet is increasing, rather than decreasing, is ample cause for¬†celebration.–April Moore
photos by Andy Schmookler
Friday, April 16th, 2010
¬†¬†¬†¬† I confess;¬† I am a worry wart.¬† Sometimes¬†at night, a thorny problem looms large and keeps me awake. ¬†Last night was such a night, and so I arose this¬†morning feeling tired.¬†
¬†¬†¬†¬† I knew just the antidote.¬† I got¬†dressed¬†and walked down into the forest.¬†¬† Low in energy, I simply lay on the ground.¬† The earth supported me, and slight breezes touched my forehead and hair.¬† Immediately I was soothed.¬† All that had bothered me during the night softened and faded into the background.¬†¬†
¬†¬†¬†¬† Calmed and happy, I gazed upward.¬† In the high, high tops of the chestnut oaks, little, yellow-green leaves¬†fluttered and waved in the sunshine.¬†¬†How new they looked, with their diminutive size and yellowish color.¬†¬†There is indeed something special about¬†leaves when they are young, fresh out of the bud, before they have reached their ¬†darker green, summer maturity.¬†
¬†¬†¬†¬† And now that I was feeling refreshed,¬†I decided to get up and see how¬†the baby leaves of some of the other trees in the forest were coming along.¬† I started with a¬†visit to a nearby¬†white oak.¬† Little groups of¬†very thin, green leaves fluttered together at the tips of its twigs.¬† I couldn’t resist handling one of the¬†little groups.¬† But in my attempt to¬†separate two of the leaves, who had yet to pull apart and lift upward, the entire¬†group of leaves¬†came off in my hand.¬† I was briefly aghast, having destroyed such¬†youth and complexity.¬† But as I looked about at the many other little clusters of leaves dotting the¬†tree’s twigs, I reminded myself that my clumsiness wouldn’t cost the tree much.¬†¬†¬†
¬†¬†¬†¬†¬†¬† Then there are the red maples, always worth a visit.¬† While these leaves have been growing for more than a week now, most are still slightly folded downward, flimsy and soft to the touch.¬† They too will soon firm up, and stretch outward and upward.¬†
¬†¬†¬† Another one of my favorites is the tupelo.¬† Never are its leaves droopy;¬† they start out perky, pairs of them opening upward together.¬† But now that they are getting bigger, they seem to be relaxing outward, closer to the¬†mature leaves they will become than to¬†the babes they have just been.
¬†¬†¬†¬†¬†Just a few steps away was a little pine tree.¬† At every¬†single tip of its flexible branches was a small, yellowish growth, covered with tiny, rubbery ‘spikes’ destined to become¬†green needles.¬† Now these rubbery little points are but a hint of¬†what is to come.
¬†¬†¬†¬†¬† And finally, the moosewood.¬†¬†The little tree’s delicate branches were dotted with¬†buds, broken open by tiny leaves pushing their way out.¬† Pressed together, the emerging leaves seemed to be striving forward, out into the world.¬†¬†Many of the moosewood’s leaves were already fully out, their bud covers peeled back, their work finished.¬† These¬†shiny, bright¬†green leaves were already a good size, although they will grow much bigger still.¬†¬†With a pleasure that surprised me, I stroked a moosewood leaf between my fingers.¬† How moist and bright green, how light and flexible.¬† The depth of its¬†many veins made the leaf seem more three-dimensional than two.¬†¬†¬†
¬†¬†¬†¬† Feeling the little moosewood leaf so new, so full of life, I imagined the leaves around me as not that different from human skin–so soft and silky at the start, gaining firmness with maturity, and finally losing¬†suppleness,¬†drying, cracking, and¬†becoming discolored in¬†old age.¬†
¬†¬†¬†¬† But for now, it is the beauty of youth¬†that reigns in the forest.–April Moore
New pine growth--photo by April Moore
Tuesday, April 13th, 2010
¬†¬†¬†¬†Earth Day¬†is Thursday, April 22.¬† This¬†year marks the 40th anniversary of the¬†very first Earth Day in 1970, and the earth needs your help now more than ever.¬†
¬†¬†¬†¬†¬†About a billion people in more than 190 countries are expected to participate in some sort of¬†Earth Day action to¬†help bring about a healthy, sustainable planet.¬†¬†Many of¬†these actions will take place on Thursday, April 22, while others are planned for the weekend before or after Earth Day.¬† Some groups are even planning an entire¬†Earth Week of¬†varied activities to celebrate, educate, and advocate on behalf of the planet.
¬†¬†¬†¬† Neighborhood and beach clean-ups,¬†habitat restoration activities, visits to state legislators, climate teach-ins, tree and milkweed planting, recycling of prom clothing,¬†and a¬†solar cookout are just a tiny fraction of events planned around the country.¬†¬†
¬†¬†¬†¬†¬†In addition to the scores of¬†activities going on in towns and cities across the U.S.,¬† there will be a nationwide action¬†in Washington, DC.¬† Concerned Americans will join together on the National Mall on Sunday, April 25, to urge Congress to enact¬† comprehensive climate legislation.¬†¬†
¬†¬†¬†¬† Find out how you can celebrate our earth by getting involved in¬†constructive action on its behalf.¬† By visiting the Earth Day Network’s website, www.earthday.org, you will find information about events planned near where you live.¬† And, if you wish, you can register your own event.–April Moore
Friday, April 9th, 2010
¬†¬†¬†¬† Yellow, it appears, is¬†the color that announces spring.¬† The earliest bloomers¬†I notice around me¬†are all the yellow ones.¬†
¬†¬†¬†¬† This year, unlike past springs I can remember, the daffodils were first.¬† Even before this winter’s deluge of snow had completely disappeared, the bulbous tips were pushing their way up out of the wet soil.¬† And as these perennial harbingers of spring grew and opened in their bright, creamy-smelling yellowness, I remembered why the spring feels like such a gift after months of winter.
¬†¬†¬†¬† Right along with the daffodils, or just slightly later, came the forsythia.¬† Wild¬†and rangy,¬†with a¬†Van Gogh-like, mad energy,¬†these bright yellow branches charged this way and that, along the driveway, along the road.¬† Now they are being tamed by the growing green along their branches,¬†their wildness transforming into¬†just another staid, green bush.
¬†¬†¬†¬† Then there was spicebush.¬†¬†The forest where my friend and I hiked recently was¬†still mostly¬†leafless and brown.¬† But tiny, floating globes of¬†soft yellow dotted our views, near and far– the blossoms of these woody shrubs.¬†¬†I like the name ‘spicebush.’¬† It conjures up¬† inviting cooking smells.¬† But, in fact, I find the spicebush scent¬†an astringent one, similar to witch hazel, another yellow bloomer.
¬†¬†¬†¬† Finally, in my tribute to yellow, comes coltsfoot.¬† The name of¬†this dear,¬†unassuming little flower is about as¬†sweet¬†as the plant itself.¬† Someone, sometime,¬†must have likened this narrow,¬†close-to-the-ground, little bloom to the foot of a very young horse.¬† This year it was a relief to finally see some coltsfoot along the road at the top of our ridge, long after the other yellow flowers had already bloomed.¬†¬†Usually,¬†coltsfoot is the first spot of color along the road in the early spring.¬†¬†But¬†this year, for some reason, it showed up last among the yellows.
¬†¬†¬†¬† Now, the early spring yellows are giving way to the later spring pinks–redbud, magnolia, cherry blossoms.¬† God, spring is wonderful!–April Moore
Friday, April 2nd, 2010
¬†¬†¬†¬† A warm and sunny spring morning.¬† Does it get any better than this?¬†
¬†¬†¬†¬† Since I was up earlier than usual today, I decided it was a perfect time to get outside and see what I could see.¬† And I was richly rewarded.¬†
¬†¬†¬†¬† As I stepped out into the driveway, I was treated to varied and sweet twitterings.¬† Would that I could tell one bird’s call from another’s.¬† I was never¬†good at distinguishing the different instruments in an orchestra either.¬† But no matter.¬† The different¬† birds’ songs filled the air with a sweetness that touched my heart.
¬†¬†¬†¬† Glancing about, I noticed some birds, tiny in the distance,¬†dotting the highest branches of a chinkapin oak.¬† At such a distance, I couldn’t distinguish their species.¬† But the binoculars soon revealed them to be goldfinches.¬† Bright yellow males and¬†dull,¬†vaguely yellow females perched here and there at the tips of twigs.¬† A few sat still, and a few flitted about within the tree.¬† Most, however,¬†appeared to be eating the buds at the end of the twigs.¬†¬†One male even hung upside down from a twig, the better to get his beak around a bud.
¬†¬†¬†¬† After a few minutes, all the goldfinches suddenly flew out of the tree and soared, high overhead, off into the distance.¬† Then, moments later, they were all back again (unless it was¬†others who looked just like them).¬† They resumed their activities in¬†the first tree, just¬†as before.¬†¬†Why had they suddenly left?¬† And why did they so suddenly return?¬† And why do they seem to like only the chinkapin buds, and not those of the nearby chestnut oak or the red maple?
¬†¬†¬†¬† Although I was craning my neck to keep the binoculars focused on the goldfinches so far up in the tree, it was a treat to see them so clearly.¬† I am a new convert to binoculars.¬† Until I watched birds with my Master Naturalist class last weekend, I had found binoculars to be a hassle, difficult to adjust properly and an annoying extra appendage.¬† But I no longer feel that way.¬† Now that I’ve taken the binoculars¬†out of their box for the first time in years,¬†I won’t be putting them back¬†anytime soon.¬† They are parked by a window, ready to be picked up whenever an interesting bird comes into view.–April Moore
a male American Goldfinch
chinkapin oak with spring buds--April Moore