Why Do Leaves Change Colors in the Fall

Why do leaves change colors in the fall

Leaves are an important part of any tree.  During the spring and summer, the chlorophyll inside them uses sunlight to turn water and carbon dioxide into oxygen and sugar in the form of glucose in a process called photosynthesis.  Like an animal preparing for hibernation, plants create extra glucose to help them through the winter.  As the shorter, colder days of fall begin, plants must consider what to do with their leaves.  Some plants, called evergreens, have leaves built specifically to survive the winter, either with minimal surface area or waxy coatings.  Other trees prepare to lose their leaves, but as they do they create a wonderful palette of color.

Greens, yellows, and orange

The green found naturally in leaves is created by chlorophyll.  Another chemical in leaves, called auxin, maintains a part of the leaf called the abscission layer.  As fall begins, the cooler days prevent the creation of more auxin.  The abscission layer grows and prevents the tree and leaf from sharing any more water or nutrients.  Without water, chlorophyll begins to fade, allowing other colors to show through.  Oranges and yellows are often already present in the leaves, in the form of carotene and xanthophyll.

Reds and purples

Some trees, like maples, use glucose trapped in the leaves to create a chemical called anthocyanin.  Some scientists have suggested anthocyanin may help a tree keep its leaves longer, as it lowers the freezing point of the leaves.  This may allow the tree to collect as much nutrition from the leaf as possible.

Browns

Brown colors in leaves are caused by a waster product named tannin.

Where to find the best colors

Weather plays a large role in color production.  In order to produce the best colors, the trees need to experience a warm and wet spring, followed by a temperate summer and an autumn with bright sunny days and cool nights.  The national forest service provides a hotline which offers information about the best color displays.  The scenic byways in thirty-one states have also been designed to best display the fall colors.

When looking for a particular color, keep in mind that colors are often characteristic of a species.  Oaks, high in tannins and anthocyanin, are often reds and browns.  Hickory leaves turn a golden bronze, while aspens are golden yellow.  Dogwoods can nearly be magenta, with their combination of purple and red.  Beech trees typically have tan leaves.  Black tupelo leaves are crimson red in the fall.  Maples vary by species.  Red maples, with their extra glucose, turn scarlet.  Sugar maples allow a little more of the carotene to shine through and are a fiery orange-red.  Black maples are a brilliant yellow and striped maples nearly lose all their color.

Not a leaf wasted

The abscission layer of the leaf eventually loosens the leaf enough that it will fall easily.  These leaves serve as food for all sorts of decomposers, which in turn help to restock the nutrients in the soil and help hold water.  Scientists have also proposed that chemicals like anthocyanin in leaves may help avert the growth of other species.

For those that love the fall colors, and would like some science experiments to accompany a leaf exploration, Science Made Simple has some great experiments.

http://www.sciencemadesimple.com/leaves.html

http://www.na.fs.fed.us/fhp/pubs/leaves/leaves.shtm

http://dnr.wi.gov/org/caer/ce/eek/veg/trees/tresstruecolor.htm

http://www.esf.edu/pubprog/brochure/leaves/leaves.htm

Talk Like a Pirate and Welcome to Fall

We began the week celebrating Talk Like a Pirate Day.  My husband was stationed in Hampton, Virginia before where I taught at the local history museum about Blackbeard and a Blackbeard Festival was held so we are well versed in pirates.   I also worked at the Duke Energy Children's Museum at the Cincinnati Museum Center while the Real Pirates exhibit came through.

Some interesting pirate facts to share.

• It was actually bad to be a well-known pirate, because that increased the number of people hunting you down unless you were a privateer like Sir Francis Drake who had the protection of the crown because he only attacked ships of political enemies of his home country.  
• There were some female pirates, but they often disguised themselves as men.  Anne Bonny and Mary Read both served with Calico Jack.  One night, their ship was attacked by the Navy and many of the men were too drunk or scared to fight but Anne and Mary tried to fight.  The men were hung for the crime of piracy, but the women were both pregnant so they were sent to prison.  No one knows what happened to them then.  
• X marks the spot comes from Treasure Island by Robert Louis Stevenson.
• There is no evidence of a pirate walking the plank.
• Life as a pirate was rough, but there was a pirate code that tried to keep things fair in the ship.  The treasure was divvied up by the quartermaster according to the rules.
• The Jolly Roger was not the only pirate flag.  Pirates often created their own flag to identify themselves to other pirates.  

We started with some pirate stories.  Pirate Princess is about a girl who wants nothing more than to give up being a princess to become a pirate.  She struggles at first with the hard work, but soon uses her skills at finding treasure to impress the crew.  Victricia Malicia, on the other hand, was born into a pirate family but didn't feel like she belonged.  All she wanted to do was read.  In Pirate Girl, a group of ferocious pirates capture a little girl at sea.  She tells them they will regret it, and they do, when her mother's band of pirates attack.  Roger the Jolly Pirate is a fun take on how the Jolly Roger came to be known as the pirate flag.  It's written and illustrated by the same guy who illustrated the Lemony Snicket Series of Unfortunate Events.

We created our own island to bury treasures using a silicon ice cube tray.  First we added beads for treasure.  Then we buried them using a combination of baking soda and dyed sand to represent different parts of the island like sand and plants.  We used some watered down liquid water color to represent water.  The silicon tray made it easier to do the next part, where we created a map of our buried treasure.  The tray provided a nice grid for us to start from.  Then came the hard part, remembering where our treasure was buried so we could mark it on the map.  Then we took our island to the sink, where we used vinegar to wash away everything to reveal the treasure.  It's great to include mapping skills with pirate themes whenever you can.

We also created our own pirate flags.  I gave Genevieve the choice of dark felt or black paper.  She chose black paper and glitter glue, although we could have used chalk as well to get a nice image.  After Genevieve made her own flag, I had her talk me through things I should include on my pirate flag to let people know that I am coming.  We played her Jake and the Neverland Pirates matching game as well.

Other great pirate activities to do at home include creating treasure chests, playing pirate dice. or creating your own scrimshaw.  Pirate dice, or liar's dice, is the game played in Pirates of the Caribbean.  Each player should have a cup and 5 regular dice (6-sided).  Shake the cups, then place them upside down on the table.  Each player may look at their own dice.  Then the first player will use the number of ones in their cup to guess how many ones there are on the table.  The next player can increase the number of ones they think there are or guess the number of twos.  Once a player moves on to the next number, players may not go back to guess previous numbers.  At any time a player may call another player a liar if they believe they have overestimated the total of the current number.  Scrimshaw is beautiful carved artwork.  And although I wouldn't recommend carving into bones with your kids, you can carve soft white clay or create plaster medallions and cover them with wax that is easy to carve.

We also have been celebrating the start of fall.  We read Stellaluna, as well as Verdi and Pinduli by Janell Cannon.  Stellaluna is about a bat that spends some time living with birds.  We read 5 Little Pumpkins, The Fierce Yellow Pumpkin, and Ready for Pumpkins as Genevieve loves pumpkins.  On a similar vein, we read Sophie's Squash about a little girl who adopts a squash as a plaything.  We also enjoyed Storm is Coming and In the Leaves which is a great story where a boy explains some Chinese characters while on a trip to a farm with friends.

We did some great art and science experiments.  First Genevieve made a fall wreath and garland from a pumpkin cut out kit.  We decided to color some plants, so we split the bottom of a piece of celery with leaves and placed each side in a cup with different liquid watercolor.  We also placed a white carnation in red liquid watercolor.  All the watercolors were watered down.  We watched to see throughout the day how the plants might change.

We also did a little chromatography.  Ours didn't turn out because my lab assistant wanted to add a lot of water, but you might have better luck if you try.  First we tore up two groups of leaves - one that had changed to red and one that was still green.  You could also grind them up.  Add a bit of rubbing alcohol (use with care as it is flammable and not something you want anyone drinking).  Then we added a bit of water (warm water will help speed up the process).  Let that sit a bit, while you prepare a coffee filter by cutting it into strips.  When the water is colorful, dip the tip of the coffee filter into the liquid and you can watch the color travel up the strip.  Colored stripes should stop at different points along the filter.

We tried candy chromatography as well.  I'd recommend Skittles, but you can use M&Ms or gummies too.  We used a similar technique to the leaves, to which of course we added too much water.  Another option is to wet the candy a bit and use the liquid to draw about half way up the coffee filter strip.  Dip the tip in water and a little bit of rubbing alcohol and watch as the liquid separates the colors used to make the coating.

We did a little math first with the Skittles.  We opened the pack and sorted them by color into little cups.  We guessed which color had the most candies.  Then we drew a chart to see which color actually had the most candies.

Grandparents Day, Onam, and Fall Lantern Festival

We started the week talking with our grandparents and remembering some of our favorite moments with them.  She remembers sharing apples and strawberries, reading stories, exploring new places, building and making videos.  We've read lots of books about spending time with grandparents.  In Tambourine Moon, a grandfather walks with his granddaughter through the city at night while telling the story of the night he met her grandmother.  Tangerines and Tea, My Grandparents and Me is an alphabet book about staying with grandparents overnight.  Llama Llama Gram and Grandpa is also the story of an overnight visit with grandparents, as well as a forgotten lovey.  This is one of Genevieve's favorite series.  The author recently passed away from brain cancer, and I recommend reading one of her books with a child in honor of her life.  In Max and the Tag-along Moon, Max watches the moon follow him home, feeling his grandfather's love the whole way.  In Grandma's Smile, a little boy travels to find his grandmother's missing smile.  The Mitten is about a lost mitten, knitted by a grandmother, and serving as a temporary shelter for several creatures.  Silas's Seven Grandparents is a book about the fun and challenges of having several grandparents.  Grumpy Grandpa was a favorite, about a grandpa who has forgotten what is like to be a kid.

Onam is a festival in Kerala, India.  Long ago, Mahabali defeated Indra and became ruler of all of Indra's territory.  He is believed to have been a good leader in Kerala, treating people equally.  The people were happy and without worries, no children died, and there wasn't any lying or theft.  However, as great as he was for the people the demigods were not happy with his rule.  Vishnu came to him in the form of a dwarf.  Mahabali promised him a gift and Vishnu asked for no more than three steps of land.  Mahabali agreed and Vishnu grew and stepped over heaven and earth.  Mahabali kept his word as a man of honor, and is allowed to visit each year at Onam.  People celebrate by creating designs in their yard using flowers, wearing new clothes, cleaning out their house, dancing, feasting, and participating in the great snake boat race.  It is also a time of thanksgiving, celebrating the harvest with a great vegetarian feast.

We didn't have a lot of flowers left, but we did have some colorful sand, so we went outside and created a sand painting.  We also read the colorful My Mother's Sari, celebrating the beautiful patterns and colors.  It also includes instructions as to how to wear a sari.

The Lantern Festival goes by many names throughout Asia - Chusok and Trung Thu being some of them.  It is a festival of thanksgiving and celebrating family.  Each country may celebrate it slightly differently, but it is held on the 15th day of the 8th lunar month.  This year it coincides with the full moon on 16 September.  Celebrations often include a visit with family and special moon shaped foods, like rice cakes, moon cakes, and pomelos.  They remember ancestors they have lost, visiting their gravesites and burning incense and paper gifts.  Families celebrate each other and the harvest.  That night they use lanterns and candles to represent the light of the moon.  Children might wear masks, sail boats, and watch unicorn dances.

We've been studying the moon this week, noticing it's size and shape and watching to see if it follows us.  We noticed it's up in the afternoon, but we can't see it in the morning anymore.  We read Ba Nam, which is an older book but it follows a family visiting the ancestral plots.  We also read The Sun, the Moon and the Gardener's Son, which is a fable with the sun, moon, and rainbow fairies.  The Moon's Almost Here is illustrated by Tomie dePaola and says goodnight to several animals as mime Pierrot and his child prepare for bed and watch the moon.  Thanking the Moon is a nice book for younger kids that follows a family at their mid-autumn moon festival.

What else is new?  Genevieve has been practicing counting (3,1,7,8,9) and riding her tricycle all by herself.  She is good with colors and shapes, body parts and the letters G and T.  She also likes to remind me that her arm is happy, because I told her about her humerus when she hit her elbow.  She's really interested in her calendars, both to review what we are doing each day and to see the month's activities.  She's looking forward to the day airplanes and birthday cake show up on the calendar to show family will be coming to visit for her birthday.  We've started a new round of classes - storytimes, dance, music, gymnastics and soccer.  Tobias is pulling himself up all the time, and trying to stand on his own.  When he's not trying to stand, he's usually crawling.

Labor Day

For the week of Labor Day, we are reading about different jobs people do, hunting for jobs we see everyday, and pretending to have different jobs.

We started the week talking about church figures and how they help the people in their church.  We read Patrick: Patron Saint of Ireland.

We read about business owners in The Lorax, Uncle Jed's Barbershop, Daniel Tiger's Nighttime in the Neighborhood, Walter the Baker, and The Sneetches and Other Stories.  We went walking around a shopping center and noted a lot of different businesses.  Genevieve played store owner and sold me different things.  She also played baker and made cake for everyone and became a hairdresser.

We read about entertainers in The Clown of God, Zin Zin Zin a Violin, and The Story of Ferdinand.
We created artwork and cards.  She painted a park at night and a rainbow.  Tobias painted himself.












We talked about daddy's job and read While You Are Away.  We talked about how the military's job is to help keep us safe, like some other community helpers but sometimes that means traveling far from home.  We pretended to be airplanes.

We talked about other community helpers like doctors, mail carriers, firefighters, librarians, and police.  Genevieve pretended to be a doctor.  We read an excellent book for this weeks theme: Clothesline Clues to Jobs People Do.  We also read books like A Fire Drill with Mr. Dill, Police! Hurrying! Helping! Saving! and Firefighters! Speeding! Spraying! Saving!.  We read Clifford visita el hospital, which is a fun book for some Spanish introduction.  Another excellent book for this week was Grandfather's Work, which talked about traditional healing in Nigeria, as well as some other jobs family members might have like bakers, lawyers, doctors, blacksmiths and potters.  Then we were the greatest of community helpers, a superhero.

Back to School

This week we read all about going back to school and learned about some of the things kids are taught in school.

We started the week with some general books about going back to school.  Foxy is about a little girl who is nervous to start school the next day.  A fox with a magic tail comes by to help her get everything she needs, like pencils and notebooks.  When she is nervous that she doesn't know enough, he tries to help but she realizes she would rather learn all these things at school.  Lulu's Lost Shoes isn't really about going to school, but its about a little ladybug looking for her shoes so she can go to school.  It's a We Both Read book, which means it is designed for the parent to read one side of the page and the child to read the opposite page.  My New Teacher and Me is by Weird Al Yankovic and stars a precocious little boy meeting his new teacher.  His new teacher is very strict and by the book, and doesn't take to the brilliant, imaginative mind of Billy.  But by the end, they realize they can learn from one another instead of being in opposition.  If You Take a Mouse to School is another in the series by Laura Numeroff.  This time the mouse heads to school where he does math, spelling, science, building and writes a book.  Pete the Cat Rocking in My School Shoes follows Pete through a day at school.  Even when faced with all sorts of new experiences, Pete doesn't worry and just sings his song while rocking in his school shoes.

We started the week with some art, talking about colors and how they can be combined.  We played with colored sand and glue, glitter glue and dot markers to create our own works of art.  We also read Pete the Cat I Love My White Shoes and Mix It Up.  Genevieve loves identifying the colors in Pete the Cat and the interaction in the Herve Tullet books.

We sang the alphabet song and identified what letter different words start with as well as played with our alphabet foam flooring.  We read Miss Bindergarten Gets Ready for Kindergarten, one of many in the Miss Bindergarten series.  Joseph Slate found a different animal for each letter of the alphabet, and these children all attend Miss Bindergarten's class.  This one is an introduction to the animals and school.  We also read Bill and Pete, in which Bill is just starting school and learning the alphabet and how to spell his name (William Everett).  Finally we read Animalia.  Animalia is amazing for its artwork, its alliteration, and its hidden images.  Graeme Base included many examples of each letter hidden in the scenery for each letter.

We practiced counting 1-10, used our balance scale, divided our cake and identified shapes in our foam floor tiles.  She loves to count 3-1-7-8-9.  Genevieve asked to play her matching game a few times.  We listened and sang along to They Might Be Giants Here Come the 1,2,3s.  We read The Very Hungry Caterpillar, which is a great text for an introduction to metamorphosis and includes counting up to 5.  Amazingly we found a caterpillar Tuesday too.  In Miss Fox's Class Earns a Field Trip, the class practices addition and subtraction as they stumble through earning the money for a field trip.  We read two Miss Bindergarten books - Miss Bindergarten Celebrates the 100th Day of Kindergarten and Miss Bindergarten Takes a Field Trip with Kindergarten.  The first celebrates the number 100 and the second is a shape hunt as they travel through the town.  Genevieve loves Pete the Cat, so we read Pete the Cat and his Four Groovy Buttons.  This is a fun introduction to the simplest of subtraction.

Wednesday we practiced health as we walked to the park.  We read Miss Fox's Class Shapes Up and Miss Bindergarten Stays Home From Kindergarten .  Miss Fox teaches her class methods to stay fit while Miss Bindergarten and some of her students take sick days.  Thursday we went to the zoo, making a hypothesis that we would be able to see more animals because we were going earlier than the week before.  We read Dig In, a book about observations in the dirt of the yard and Miss Fox's Class Goes Green, where they learn to reduce their footprint, reuse, and recycle.

Friday, we read worked on our calendar and looked at photos from our family past.  On Saturday, we went to our first nerdy convention, but didn't have the patience to stay long.  Seeing so many grown ups dressed up in costumes was a little overwhelming for Genevieve and the lines were to much for Tobias.