Autumn the Colourful Equinox
Autumn is a wonderfully colourful time of year that is enjoyed by gardeners and non-gardeners alike. From the tall stands of drying grasses, to the late blooming perennials, there are subtle earth tones to the bright and bold shades. Certainly in Ontario, Canada where I call home, even the trees shout out their presence. Each limb is full of coloured leaves that put on quite a show before they drop to the ground, hence the term fall.
Recently, watching the neighbours piling theirs along the curb to be sucked up and taken away, I was wondering about the countless others who were doing the same, or merely admiring the colours of fall. Either way we all know that colder weather is coming. For gardeners the temperature change also means it is time to put the gardens to rest with winter protection of some sort.
What to do with all those leaves?
Speaking for myself, I leave my leaves alone. Of course with seven tall evergreens on my property, only the wind delivers them from the gardens around me. In fact if I rake at all, it is to put a layer on my garden with evergreen boughs on top to hold the leaves in place for additional protection. Despite this being my ritual, gardening sources present two different viewpoints about using leaves for winter garden protection.
Some believe any disease on the leaves will transfer to the soil and plants that will grow there in the spring, while others believe they will help provide a more even temperature throughout the winter and keep strong winter winds from drying out the soil. The one thing both schools of thought share is that oak leaves break down very slowly and are best left off gardens and out of any compost pile.
Speaking of mulch, I think it is very nice of my neighbours to rake up their leaves nicely, for me to mulch. I do not compost them but neatly transfer those soggy leaves in to green garbage bags and put them on my back patio in a sunny spot. Quite by accident (or should I say laziness) I left several bags over the winter until early summer and discovered they had mulched quite nicely. The sun’s rays and the dark plastic helped the damp leaves form lovely rich compost.
What a gorgeous view!
Putting all uses aside, today seeing trees full of coloured leaves, the yellows through to red shades, mixed with each other, certainly made me wonder why and how they change to such magnificent shades. Again, I resorted to my gardening books and the internet to find the facts I probably learned many years ago in school and have since forgotten. Fall splendor is nothing more than good, old fashioned chemistry, whether here or on the other side of the world. Yes, the Northern Hemisphere worldwide gets to share in the lovely Fall or Autumn leaf colour changes from September through to late November.
Photosynthesis is a term most of us learned in school, from the Greek words “photo” or light and “synthesis “which means putting together. This process, describes how most plants and trees make food for themselves. Like many other scientific processes, it is complicated when studied in depth, but has quite a simple explanation. Water in by the roots, plus Carbon Dioxide from our air are the basics need for sunlight and the green chlorophyll in leaves , to form two major compounds.
The first is oxygen which is given off and purifies the air around us, and the second is Glucose. Yes my dear, leaves produce glucose for immediate use as energy and some is stored for later use. Of course unlike in humans, the storage is beneficial and does not increase pants size or cause health issues.
Instead the stores are used once the September equinox arrives and the weather changes. While temperature is a factor in slowing photosynthesis, the decreased amount of UV in the suns rays shuts off the green chlorophylls food making ability. Then the stored glucose which is trapped in the leaves begins to turn red. Also now visible are orange carotenes and yellow xanthophylls which were hidden by the green.
Certainly leaf colour cannot by itself be a guide to trees but if you are looking for a tree that produces a specific colour palette in the fall, here is a general guideline. Of course checking with a local nursery would certainly help or finding a good sourcebook or on line.
Red Leaf colour
Red Maple trees are known to produce the brightest red leaves, as does the shrub called the Burning Bush. Additionally a few other maples including Japanese, turn a lovely shade of red, as do some oaks such as Red, Pin and Scarlet, Dogwood, Sassafras and Sweetgum to name a few. Let’s not forget the Japanese maple!
Yellow and orange Leaf colour
Some of the trees known for yellow and orange leaves are Hickory, Ash, and some Maples, Poplar, Tulip Tree, White Oak, a number of Japanese Maples and Chestnut. Also some Sassafras, Sweetgum, Beech, Birch and Sycamore foliage changes to lovely golden hues tones between the yellow and orange shades.
Gardeners always find something to do each season and as we are not weather persons, I will not try and be one now. However, not until the digging bug better known as curiosity, picked at my brain again, did I really think how Geography of about Equinox, Hemispheres and latitude.
Equinox from Latin “aequus” or equal and “nox” which is night is the day in September when the Northern Hemisphere, or half of the Earth, has equal hours of day and night. As the planet we call home, shifts while it spins, we in the northern side get tilted back from the sun’s rays while the south moves forward for more. This means the Southern Hemisphere is planning and planting their vegetable gardens while we are putting ours to sleep.
Hemisphere comes from two very long Ancient Greek words that translate to mean “half of a sphere. Here on the earth using latitude or longitude (north to south division) there are four map based hemispheres. The North-South the division is the equator and East-West the dividing line is the prime meridian
Combining fall experiences from across the world would be interesting but staggering by volume. Instead, I remembered my globe and decided to follow the approximate latitude of Ontario, Canada to find out what Fall looks like around the world. Latitude is the system of parallel lines that are used to mark a position on the planet, from east to west with the Equator being Zero degrees and the North or South Pole being Ninety degrees.
WWF- World Wide Fall
Fall comes to most of the world but not all at once. In the Northern Hemisphere, September, October and November are considered fall, which is the hottest time for the Southern Hemisphere. Then during March, April and May when the northern half of the planet is beginning its growing season, people in the south experience Fall.While there is some variation across the globe, East to West and closest to the Equator, almost every continent experiences seasonal foliage colour changes, as the temperature drops and sunlight diminishes.
Using my finger as a pointer, I traced my way through countries from west to east, writing their names on a list as I circled the earth. Then I began digging through my photographs and the wonderful world of Wikepedia , leaving you with the inspirational colours of to leave you with an inspirational tour of Autumn around the world!