The colours autumn - Forestry Commission · The colours of autumn Autumn colours are influenced by...
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The colours of autumn Autumn colours are influenced by the weather due to the effect different conditions have on the chemicals in the leaves. But how do these chemicals give us autumn colours? The Forestry Commission explains. During summer leaves already contain most of the colours of autumn, however they are “covered up” by the dominant green chlorophyll. Chlorophyll is the green pigment in plants that harnesses energy from sunlight to combine water and CO 2 to create sugars (plant food). As the weather cools and the leaves start to receive less sun, the tree realises that winter is about to begin. Chlorophyll breaks down and the new, colourful pigments takeover giving us beautiful autumn displays. Orange Orange comes from beta carotene – one of the most common compounds in plants. One of the best trees to see carotene in action during autumn is Sweet Chestnut. Carotene, as its name suggests, is also the chemical responsible for giving carrots their unique colour. forestry.gov.uk/ autumn Forestry Commission Woods & Forests @ForestryCommEng #Autumnleafwatch Red The red colour is unlike other leaf colours as it hasn’t always existed in the leaf. The colour is caused by anthrocyanin pigments which are formed by a reaction between sugars and certain proteins in cell sap. If the sap is quite acidic, the pigments impart a bright red colour. If the sap is less acidic, then the resulting colour is purple. Japanese maples produce plenty of anthrocyanins and have really bright red leaves. Green During the spring and summer months, leaves are filled with green chlorophyll which helps trees to harness the sunshine and turn it into food. To survive the winter, most trees will shut down to store their sugars. A cork-like membrane develops between the branch and the leaf stem, depriving the leaves of nutrients and breaking down the chlorophyll. Yellow The yellows of autumn leaves come from xanthophyll pigments and can be seen throughout autumn in a variety of trees including birches, beeches, ashes and field maples. The yellow colour of egg yolks are because of the xanthophyll in plant products, eaten by the hens.
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Transcript of The colours autumn - Forestry Commission · The colours of autumn Autumn colours are influenced by...
The colours of autumnAutumn colours are influenced by the weather due to the effect different conditions have on the chemicals in the leaves. But how do these chemicals give us autumn colours? The Forestry Commission explains.
During summer leaves already contain most of the colours of autumn, however they are “covered up” by the dominant green chlorophyll. Chlorophyll is the green pigment in plants that harnesses energy from sunlight to combine water and CO
2 to create sugars
(plant food).
As the weather cools and the leaves start to receive less sun, the tree realises that winter is about to begin. Chlorophyll breaks down and the new, colourful pigments takeover giving us beautiful autumn displays.
OrangeOrange comes from beta carotene – one of the most common compounds in plants. One of the best trees to see carotene in action during autumn is Sweet Chestnut. Carotene, as its name suggests, is also the chemical responsible for giving carrots their unique colour.
forestry.gov.uk/ autumn
Forestry Commission
Woods & Forests
@ForestryCommEng
#Autumnleafwatch
RedThe red colour is unlike other leaf colours as it hasn’t always existed in the leaf. The colour is caused by anthrocyanin pigments which are formed by a reaction between sugars and certain proteins in cell sap.
If the sap is quite acidic, the pigments impart a bright red colour. If the sap is less acidic, then the resulting colour is purple. Japanese maples produce plenty of anthrocyanins and have really bright red leaves.
GreenDuring the spring and summer months, leaves are filled with green chlorophyll which helps trees to harness the sunshine and turn it into food.
To survive the winter, most trees will shut down to store their sugars. A cork-like membrane develops between the branch and the leaf stem, depriving the leaves of nutrients and breaking down the chlorophyll.
YellowThe yellows of autumn leaves come from xanthophyll pigments and can be seen throughout autumn in a variety of trees including birches, beeches, ashes and field maples. The yellow colour of egg yolks are because of the xanthophyll in plant products, eaten by the hens.
