Why do leaves change colour
Bencito the Traveller photo
Leaves change color when chlorophyll, a substance plants use to turn light into sugar that makes a leaf look green, is breaking down and the plant is not rebuilding replacement molecules as the days get shorter. Other pigments, a class called the carotenoids, show as yellow and contribute to the appearance of orange and brown.
Carotenoids are always on some level in the leaf, but instead of being overwhelmed by the green as they are in the summer, they appear as the chlorophyll, and thus the green, fades away. Reds are from a more ‘expensive to make’ pigment, anthocyanin, and they develop in fall. The reds and yellow together give us the orange fall colors in some tree species.
The big factors that affect the colours we see are the length of day, temperature and the weather. The change in the length of day triggers several processes to get ready for the autumn and winter. These changes can influence the shift in color to occur. Temperature can induce or accelerate those changes. Light also plays a role. Light energy is used to make anthocyanin, so sunny days can intensify the color development.
Wind and rain are mechanical forces which can cause the leaves to detach and fall. Since different tree species hold their leaves and lose their leaves in different ways, wind and rain can influence what is present in the plant community color palette on a landscape scale. https://www.rutgers.edu/news/why-do-leaves-change-color
Animals use different tactics to prepare for winter
Tony Leprieur photo
Animals need to prepare for the winter months to come. This doesn’t look the same for all animals as they’ve evolved different techniques to brave the cold and survive. Migration is common in birds, who can fly long routes across the globe pursuing warmth. Migration for elks means spending the colder months at lower altitudes, where the weather is slightly warmer.
Many animals who stick around for winter months spend their time hiding or resting in protected environments, like nests in trees or holes in the ground. Moles, who already burrow underground during warmer months, move their tunnels deeper underground to stay away from the freeze, and store snacks for rainy days in special, secret storage tunnels.
Mice, shrews, and voles spend most of their time under the snow, in subnivean tunnels in the layer between the ground and the snowpack. Here, it’s cozy as the outside world freezes over, and food is readily available in the form of plants, seeds, shrubs, and sticks left scattered around.
Other animals hoard food. Many species of squirrel forage for extra acorns, nuts, seeds, and mushrooms during the fall, hide them in secret spots, and then go back to eat them throughout the cold months. These animals like to scatter their stashes, hiding their provisions in hundreds of hollowed-out nooks and crannies in trees or underground. https://www.discovermagazine.com/planet-earth/6-different-tactics-that-animals-use-to-prepare-for-winter
Fragaria vesca, refers to the fragrance of wild strawberry
Fragaria vesca, Fragaria is from the Latin fraga the classical name used for the strawberry fruit, referring to its fragrance. Strawberry is from an old Anglo-Saxon word streowberie derived from the age-old practice of laying straw around cultivated plants to keep the fruit off the ground, or to describe how the plants are strewn across the ground.
Wild strawberries are perennial herbs that grow from a fibrous root with short rhizomes or creeping roots. They have long, slender, leafless runners, often reddish in colour, which root when they contact the soil to form new plants. Wild strawberries grow in open, well-drained places in lowland to subalpine zones. These plants can be found in fields and meadows, in disturbed areas, and in open forest.
Wild strawberry fruits are eaten by several birds and mammals, which disseminate the seeds in their droppings. Squirrels like to feast on the strawberries. Deer also favour the plants. Strawberry-leaf tea is a good vitamin C supplement. It also has various medicinal uses. For example, the root is a strong astringent and is used as a treatment for diarrhea and other digestive orders.
Herbalists suggest a tonic made from the leaves is good for the female reproductive system and to soothe inflammations of the skin and eyes. Large amounts of strawberry fruit in the diet are said to slow dental plaque formation. https://plantwatch.naturealberta.ca/choose-your-plants/wild-strawberry/index.html#
53 Degrees 30 North by Thorsten Goldberg, Kathleen Andrews Transit Garage
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