Japanese Maple & Ginkgo
Biltmore Estate November 6, 2017
Fall color in the eastern deciduous forest seems like alchemy to me; the plain green of summer becoming brilliant gold and scarlet in fall. I was amazed to learn many years ago that those colors of fall are always present, merely being masked by the chlorophyll produced in the leaves. This is mostly true, but after reading the The Science of Color in Autumn Leaves published on the website of the United States National Arboretum, I understand the process a bit better.
Did you know that yellow and orange pigments (xanthophylls and carotenoids) are present in leaves during the growing season, masked by chlorophyll, but red and purple pigments (anthocyanins) are manufactured by sugars trapped in leaves as the fall abscission process gets underway? All of these pigments break down with exposure to light or when frozen. The one color that holds is brown which is produced by tannins.
When you live in a place where fall tourism is a big component of the economy, people talk, speculate, and generally chew on what the coming fall show will be like. The intensity of the fall colors is dependent on temperature, sunlight and soil moisture. Based on the article referenced above, the ideal conditions for a good autumn display are:
- A growing season with ample moisture
- A dry, cool, and sunny autumn
- Warm days and cool, but frostless nights
- No wind or heavy rain which can shorten the display
Acer palmatum ‘Baldsmith’
Last year we had an early frost which put a hard stop to this process. Most leaves turned brown and hung on the plants for months … pretty. This year we’ve had a good, albeit tardy, color season. In particular, the Japanese Maples have been phenomenal, as have the Fothergilla and Oakleaf Hydrangea. We have had more yellow and orange than red this year, most noticeable on the red oaks which are orangey brown.
I’m sure that elevation has some impact as well. I’ve been driving to a job site in Black Mountain (higher than Asheville) the last few weeks and there is a distinct point as I get closer to Black Mountain where the mountain sides turn from lovely to simply breath-taking.
The show is fading for this year, though I still have color in a few maples, a big crepe myrtle and the oaks. A few plants color even later, such as Spirea thunbergii and Viburnum burkwoodii. I consider them an encore!
Having grown up in the Midwest I have good memories of crunching through leaves. Even though autumn is the start of a long gray landscape, I enjoy the relief from the heat and pace of summer. I don’t mind leaf cleanup – I rake not blow, and I take it pretty slow. I find something settling about the sound of rustling leaves. It’s a good time in the garden.
Gidget in the Leaf Pile
I take pictures with my phone because it’s convenient and easy. The shots are decent (click any picture to see a better display), but it is my intention that this winter I will learn to use my expensive digital camera. There, I’ve said it out loud! A few more phone shots follow:
Hydrangea quercifolia ‘Semmes Beauty’
Western View, November 6, 2017 5:35 pm