Plant trees, celebrate autumn colours
Celebrate fall colours this year by planting trees
Forestry specialist says autumn is good time to plant trees as leaves turn colour and trees enter dormancy
As summer winds down we are often reminded of the seasonal change to come by an early splash of colour in the trees. The different colours, and the reason for the change, can be explained largely by seasonal changes in the compounds within a tree’s leaves, according to Ian Jean, Forestry and Land Stewardship Specialist with Ausable Bayfield Conservation Authority (ABCA).
The green colour of leaves is due to a compound called chlorophyll in the leaves, he said. Chlorophyll is involved in photosynthesis, the process by which plants can use the sun’s energy to build sugars and other compounds from carbon dioxide and water. While trees are actively growing, leaves contain large amounts of chlorophyll which gives them various shades of green throughout the spring and summer.
When day length becomes shorter, trees stop producing chlorophyll. In the absence of chlorophyll, other pigments begin to surface. Carotenoids are responsible for the yellow, orange, and brown colours while vivid reds come from pigments called anthocyanins. While carotenoids are present all season and masked by the green chlorophyll in the spring and summer, anthocyanins are produce mainly in the fall.
Warm, sunny late summer and autumn days, followed by cool, crisp nights are thought to produce the most vibrant reds. Sun and warmth during the day leads to lots of sugar and anthocyanin production, while cool nights cause the leaf veins to begin to close off, trapping the red anthocyanin pigment in the leaves. This provides a partial explanation to the variability in colour from year to year, with other factors likely at play.
The start of autumn colours is an indication they are entering their seasonal dormant period which continues through fall, winter, and early spring. Fall and spring are the best time to transplant trees, according to Ian. “Both are good times to plant trees,” he said. “The weather is cooler and while trees are in dormancy in fall or spring, they are better able to handle the stress of transplanting.”
One common misconception is that trees planted in the fall do not need to be watered. Watering trees is important even when planting in the fall. “Trees benefit from watering during periods of heat or drought the following spring and summer,” Iann said. Trees planted in autumn have a very short period of time for root growth before winter. Watering is very important until transplanted trees have recovered a root system, in balance with their top.
Ausable Bayfield Conservation has posted its tree order form for fall 2022.
The tree order form is available online at this link:
ABCA accepts faxed, mailed, and e-mailed orders until September 16, 2022.
We accept orders accompanied by payment until September 30, 2022.
PLEASE NOTE: Autumn Fantasy Maple trees are SOLD OUT.
When planting trees in autumn, it’s important to consider winter conditions ahead. Certain trees, types of planting stock, and locations are better suited than others to fall planting.
“Frost heaving is a problem for fall planting of very small, bare-root seedlings,” Iann said. “In the fall, we handle only larger trees in pots or in root-ball-in-burlap format and we have good success planting those larger size trees.” (Smaller seedling trees are offered in the spring tree planting program.)
There is a cost to order trees through the fall tree planting program but there may be incentive grants available for some tree planting projects. Cost-share funding may be available for establishing field windbreaks, treed buffers, and other tree planting projects.
Staff are available to help with project design and to help you apply for grants. You are invited to contact staff through the website at abca.ca or to email Ian Jean at email@example.com or phone him at 519-235-2610 (or toll-free 1-888-286-2610), extension 238.