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Title: Why Are Tree Rings Lighter or Darker? Post by: Val on July 03, 2008, 04:04:33 PM Ever wondered why tree rings are different colours?
One of life's mysteries. New wood formed in a tree during spring and summer is light in color. Toward the end of a growing season, new cells formed are smaller and have darker thicker walls. The wood is more dense and darker. That annual pattern creates rings. They tend to be wider in wet, good-growing years. The thickness and darkness of the dark part (as well as the light part) can vary depending on many things in a given season: precipitation, sunlight, temperatures, and disease and insect infestations, volcanic eruptions and fire. Near the core of a tree, rings will be tighter and darker if a young tree grows up in the shade a mature forest. Soil conditions that might change over time can also affect the growth. "The patterns in tree rings tell a story," explains Erin McMurry, research assistant in the University of Missouri'sCollege of Agriculture, Food and Natural Resources Tree Ring Laboratory. "We think of tree rings as ecological artifacts. We know how to date the rings and create a chronology, so we can tell when there has been a fire or a drought occurred and unlock the history the tree has been holding for years." Tree rings have been used to understand everything from ancient droughts to hurricane activity before records were kept. McMurry and her colleague solved a longstanding mystery by studying tree rings. On May 19, 1780, it was black as night at noon. Some people in New England thought judgment day was at hand. Accounts of that day, which became known as "New England's Dark Day," include mentions of midday meals by candlelight, night birds coming out to sing, flowers folding their petals, and strange behavior from animals. The scientists announced on June 6, 2008 that evidence from tree rings reveals massive wildfires as the likely cause, one of several theories proposed after the event, but dismissed as "simple and absurd." "A fire comes along and heat goes through the bark, killing the living tissue. A couple of years later, the bark falls off revealing the wood and an injury to the tree. When looking at the rings, you see charcoal formation on the outside and a resin formation on the top that creates a dark spot," said Richard Guyette, director of the Tree Ring Lab at the University of Missouri. http://tinyurl.com/4f4srk (http://www.postsmile.net/img/29/2971.gif) (http://www.postsmile.com/) Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Phoenix on July 04, 2008, 08:23:46 PM Hello Val, Happy to know that you are still around!!
Think I have 'seen' you on B.B. ???? -- Thank You for this info: Extremely Interesting and have 'site' in favs:--- I believe we tend to overlook, the simple thing in life Today -- guess we take too much for granted and life has changed, not for the best -- but we tend to'move' with it. Perhaps as we grow older, we may well lose our 'exploring' feelings ?? Do you think that is why?? We possibly Deteriate, in mind and body -- more quickly ???? Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 05, 2008, 05:16:39 AM Hi Phoenix what is BB? Not sure if I've been there. ???
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Phoenix on July 07, 2008, 03:30:58 PM Val, Baby Boomers!! Am sure I saw you in that forum ??
A cutoff from "Yours" forum ?????? Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 08, 2008, 05:54:35 AM No, must've been my double ;D no I haven't been there, I have been to yours though.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: ansu on July 08, 2008, 08:27:39 AM Phoenix you write:
We possibly Deteriate, in mind and body -- more quickly ? I must contradict you - we just get more critical and slower. Look at our teens - to be fit they need "fitness studios" - we never needed them, we moved around by ourselves. Would you have spent such a lot of money for such a thing - me not, I joined a "Turnverein" (gym association), swam a lot and went by foot, as my father's car was not always available. Title: Re: Why Are Tree Rings Lighter or Darker? Post by: mac on July 08, 2008, 12:57:11 PM Teri,another reason we didnt need `gyms` was we had no hoovers or dishwashers or washing machines,it was a brush and shovel and the wash house,but good gossip too while you were there.lol
Some people had `dolly tubs` where you stood and possed the clothes all good excercise,if you got the time ! Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 08, 2008, 01:09:33 PM We never had cars so it was shanks pony or bus, I wasn't very fit though, I was laid up with TB for a year so exercise wasn't allowed anyway.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: mac on July 08, 2008, 10:06:26 PM Shame that Val,cant have been very pleasant in those days.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 09, 2008, 07:02:15 AM Well actually apart from the huge horrible tablets and the daily injections the hospital I was in was great. We all slept outside on a balcony and had daily school from the radio. I must admit I loved it. ;D
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: ansu on July 09, 2008, 10:45:28 AM My daughter was also in hospital for some months when she was twelve and there was a teacher coming to her twice a week. However, when she was again "ready for school" we noticed that she had enormous gaps and it took two years for her to catch up. However, on the whole I didn't have the impression she was too unhappy in hospital.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Phoenix on July 10, 2008, 03:11:54 PM There was no such thing as 'Gyms' in our young days. We all worked, Manually and at Home as well, so we earned our pleasure!! Today?? Most young people are sitting down ALL Day at Computers -- so need to do something ?? Active!!
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: william on July 13, 2008, 08:19:21 PM TRUE PHEONI, DIDNT NEED GYMS. WALKED TO SCHOOL AND BACK, WALKED TO WORK AND BACK,WE WALKED TO THE PICTURES AND DANCES, WALKED MILES TO TAKE A GIRL HOME AND THEN WALK HOME, SOMETIMES WITH A SMILE ON MI FACE, OTHERS SULKING, LOL
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 14, 2008, 07:01:04 AM I remember the rush out to get the last bus from the pictures if you got caught by the anthem, you were walking home. ;D
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: mac on July 14, 2008, 10:54:39 AM Do they still play the anthem at the cinema ?
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 14, 2008, 11:19:03 AM No I don't think so.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Phoenix on July 14, 2008, 02:32:36 PM What Anthem ??
Ah!! William, What would I give to be able to Walk properly Again?? -- Perhaps i have done Too Much and worn my nerves away in my feet ???? Title: Re: Why Are Tree Rings Lighter or Darker? Post by: mac on July 14, 2008, 03:50:31 PM Isnt it funny they say hard work never killed anyone...........who thought that one up,it might not kill you right away,but it sure wears yours bones away.
I can spot a mile away the people that have had manual jobs and the ones that have had sitting down ones. I really believe that(some) arthritis is brought on by hard labour I saw this as a child with my aunts who worked very hard in the mills and the breweries then later cleaning offices after they had retired.No top ups then ! Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Val on July 15, 2008, 08:12:06 AM You are so right Mac it does, the doctor told me, wear and tear causes arthritis. Phoenix so sorry to hear about your feet, it must be agony.Have you got one of those mobile scooters? There are a lot of them around here and they must be a boon to people who wouldn't otherwise get out and about.
Title: Re: Why Are Tree Rings Lighter or Darker? Post by: Phoenix on July 15, 2008, 09:29:28 PM Hi Val, No!! Hard Work, never hurt anyone!!
I really Enjoyed working!! No restrictions on what, How and Why?/ I was lucky being in the positions I held -- That!! I fully believe, kept me healthy, apart from taking Cod liver oil capsules, for decades -- I have No Pain, so I consider myself Lucky!! --- but in this last year or so, my body is letting me down. My balance is 'wavy'- my feet feel strange and quite hard to walk and my left hand is only working partly. -- But remember I am in No Pain I rreally am, very lucky!! Even though I have had to give up my Carpet Bowls and my Snooker and my Interests are now 'small'-- I can get out by taking 'Misty' for some short 'hobbling' walks --- I am still Happy!! I have a three wheeled frame for shopping and use a 'stick' for taking our Dog out. So I am 'A' OK!!
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