Autumn is an ephemeral time of blasting colour where the asters spark up, leaves are set a blaze,
pumpkins perch as glowing beacons, and avian migrants give birders their seasonal eye check-up and
neck workout.
If not for the sake of easing the neck pain from looking up, trick-or- treat your eyes to a fungal foray in
the forest and you’ll be surprised at all the different colours, shapes, and forms mushrooms come in.
As triumphant green chlorophyll, the star of photosynthesis, exits the solar stage to unveil the
carotenoids and xanthophylls that give off yellow, orange, and brown hues. In some plants and trees,
anthocyanins are produced from sugars and give off brilliant red and purples. On the other branch,
evergreens have a needle with a smaller surface area and a waxy coating to withstand winter and some
manufacture antifreeze proteins to protect their leaves and roots through the winter. The palette
combinations of greens, yellows, oranges, reds, purples, and browns pleasantly teases us towards the
cooler seasons and before we know it the leaves will have dropped with the temperature.
Temperature can affect red intensity. The combination of warm days and cool nights causes sugars to
become trapped in the leaves, intensifying reds. Colour can depend on the species of trees and even
indicate sex in the case of red maples. Males give off deep reds and purples while females turn shades of
yellow and orange. Orchestrated by the seasons, fall colour is the result of autumnal equinox when the
days start to get shorter.
For the tree, undergoing this process is not simply a matter of subtracting greens and adding reds but
rather a tricky response to changing seasons. Anthocyanins responsible for red maple rouge are
suspected to function as a sun-screen, an antioxidant against insect and fungal attack, or a strengthener
for leaves and stems allowing them to swallow a few more precious beams sunlight. Hormones trigger
the leaves to drop so they don’t use up the water they need to keep their roots alive over the winter.
The final sugar harvest, the recycling of resources, and the conservation of water and nutrients is an
important time for deciduous plants and trees if they’re to survive the winter. It is to our joy the shift
from the growing season to dormancy in nature is so beautifully marked across the landscape. Where is
your favourite place to go to experience fall colour?
While the colour palette of plants is played above, fungal networks beam below. Spending most of their
lives beneath the surface, fungi are an often over looked group. However, they come in a mind-blowing
array of colours, shapes, and forms with equally as intriguing natural histories. Matching the artistry
above you can find fungi with shades of blue, purple, green, red, orange, yellow, or brown as well. Many
fungi are important soil builders,breaking down organic matter and mining minerals into useable forms,
some form mutualistic partnerships with tree and plant roots providing a host of benefits to individuals
and to forests, and some are parasites that infect (mostly weakened) living trees. Not to mention, they
have had a cultural impact on human society for thousands of years due to their edible and medicinal
properties.
The things we know as mushrooms that peculiarly poke from below the soil or perch from tree limbs are
called fruiting bodies, analogous to the apple fruit, of a larger but hidden fungal network called
mycelium. The fruiting bodies produce spores, analogous to the seed, which have the potential to start
genetically new individuals. Although they’re lumped in with plants at the grocery store and in our
minds, fungi are more closely related to animals. The more we uncover about this little known group,
the more interesting and important they become.
For example, tree-partnering fungi have been shown to receive between 20-80% of the sugars that
leaves produce and, like a bank, they can store the sugars and repay them during difficult times. Fungal
networks also broker nutrients between different tree species and transfer nutrients from dying trees to
healthy young trees. Absorbing water and minerals, the things roots are supposed to be good at, are not
as good at it as we thought. Fungal mycelium is much more absorptive and covers a much greater
surface area under ground. It has been suggested that 1 square cm of soil can contain over 5km of
mycelium. To acquire nutrients fungi mine pockets of minerals in the soils, hunt and snare soil
invertebrates, break down dead animals and plants including hard to digest molecules lignin and
cellulose, or living off hosts as parasites. These nutrients get returned to the forest one way or another
in a more useable form. Mycelium not only acts like nutrient highways, shuttling nutrients through the
forest, but also as a communication system capable of warning others of an attack. In response to an
insect attack an alert sent through the network can warn neighbouring trees to get a head start in
ramping up toxic chemicals in their leaves or needles as a defense against impending attack.
Although all of these happenings cannot easily be seen, fall is evidently an active time of year above and
below the surface and a particularly excellent time to view fungi. You can see a diversity of conspicuous
fungi that decorate our different natural areas like Canatara, Lambton County Heritage Forest,
Mandaumin Woods, Karner Blue Sanctuary, and the Pinery.
Fall weather might have its ups and downs but it can easily be forgiven with sights of glorious fall colours
above or bizarre fungi below that put a show for all the action that goes on behind the scenes.
Have any fall or fungi photos? Why not submit them to the Lambton Wildlife Inc. Photo Contest? It’s
free, gives you the chance to win great prizes, and the potential to have your photo featured in Lambton
Wildlife publications.
For photo contest information check out:
http://lambtonwildlife.com/2016-photo-contest/photo-contest-faqs/
Interested in the progress of colours? Check out:
https://www.ontarioparks.com/fallcolour
https://www.ontariotravel.net/en/plan/kevin-reports
Want to ID leaves by their fall colour? Check out:
http://forestry.tennessee.edu/leafid.htm
http://www.iloveny.com/seasons/fall/foliage-report/-seasons-fall-leaf-identifier/#.WAk_0OArKM9
http://www.sibleyguides.com/2010/04/identifying-trees-by-color/