Fall Color Report: September 17, 2023

Fall Color Report for the Week of September 17, 2023

Green! Green! Green! Green! Green! Red! Green! Green! Green!

That about describes the state of the fall colors for this week. With the occasional red maple that has turned red, and the dogwoods, which are nearing peak color, the rest of the trees along the Blue Ridge Parkway (BRP) and in the mountains of North Carolina, are still quite green. However, there are some signs of the upcoming fall color season, but we still have several weeks to go before we get to peak color.

On Saturday I went to Craggy Gardens (about 20 miles north of Asheville) and on my way back to Boone I also stopped off at Mt. Mitchell State Park. These are two high elevation sites on the Parkway (Mt. Mitchell is the highest peak in eastern North America) and if anything was going to be happening this week, it would be at these two sites. 

There were lots of folks making the short hike to the top of the Craggy Garden view point. I should mention that when you get near the top, the trail splits and the one veering to the right ends up at a lower observation point but has many fewer people. While the trees that you see from the top were mostly green, there was some hint of color on the lower slopes, most likely some early turning maples or dogwoods (couldn’t make out species because the hills were too far away). 

But along the trail there was an abundance of wildflowers and two woody species that were adding a nice bit of red color: hobblebush (Viburnum lantanoides) and Mountain Ash (Sorbus americana) with its bright orange-red berries. Hobblebush is one of my favorites because the leaves turn a deep orange, then red, then purple, often in a splotchy pattern on the leaf before the entire leaf turns just one color. It’s common on this trail and also very abundant midway up the trail going to the top of Elk Knob State Park. 

Mountain ash don’t have very showy leaves and in fact, many of the leaves are dropping now, but the berries stand out from a distance, especially when viewed against a deep blue sky. Last year for some reason, despite a spectacular foliage season with bright colors, there were almost no berries at all anywhere along the Blue Ridge. But this looks to be a banner year, and they are at peak color right now above 5,000’ elevation. Although some people say the fruits are edible, they are very astringent and could be unsafe according to WebMD, so I’d advise against eating them. Leave them to the wildlife, which need them for a food resource. 

Native trees often exhibit irregular patterns across the years when they fruit in abundance, and when they do, we say that is a “mast” year (https://www.woodlandtrust.org.uk/blog/2020/10/what-is-a-mast-year/#:~:text=Every%20few%20years%2C%20some%20species,call%20this%20a%20mast%20year.) Oaks are especially known for doing this. What the cues are for determining when a tree has a mast year are still not fully understood. The prevailing theory for why trees have mast years has to do with “predator satiation”. 

In a good year, the tree saturates the environment with fruits (a single oak can drop hundreds of acorns in one square yard, for example). This in turn, provides abundant food resources for animals that eat these fruits, like mice, squirrels, and jays, and in these good years their populations build up to large numbers. 

But if all these animals eat the seeds, then there is no successful tree reproduction and that’s not good for the species. So, after a few years of good seeds, trees will have a fallow year where they produce very few fruits, like acorns. This causes a massive die off of the seed predators. If the next year is a mast year, then many of the seeds will survive because the predator populations were decimated the previous year. By doing this on an irregular basis, the predators can’t figure out which year will be a good one and which a bad one. Thus, the tree sacrifices seeds in some years to ensure they will escape predation in another year. Pretty smart tactics on the part of the tree I must say!

Back to fall color. Today I occasionally observed the lone red maple that had totally turned color. As with people, no two maples are exactly alike, and some may be genetically predisposed to turn color early, or, perhaps they may be growing on a dry or nutrient poor site and be more stressed than other trees, and hence they color up before the other trees do. Whatever the reason, they were rare on the landscape this week.

There are lots of native perennial wildflowers in bloom right now, including green-headed or cutleaf coneflower (Rudbeckia laciniata), while snakeroot (Ageratina altissima), Eastern Aromatic Aster (Symphotrichum oblongifolium, but correct me if I have mis-identified this one), maybe white heath aster (Symphyotrichum ericoides), Solidago species (several different ones, and which are difficult to identify to species), a morning glory (possibly in the genus Ipomoea), and a yellow composite (related to coneflowers, but I don’t know the species), plus others. So, while the trees may not be doing much this week, there is a profusion of color, ranging from white to blue to yellow, at ground level.

And finally, if you aim your view toward the ground, or look up at the trunks of trees, you notice all the mosses that grow at these high elevation sites. These small plants cover logs and rocks and also grow on tree trunks, and are exceptionally abundant in high elevation forests, in part because of the higher rainfall that these sites receive. 

If you go to the Fall Color Guy site you can see all the photos that are posted here, but with explanatory captions.

Mosses have been around since before flowering plants and conifers evolved (over 400 million years) and are thus very successful life forms. Yet we often overlook them due to their small stature. North Carolina is home to almost 400 taxa of mosses (https://auth1.dpr.ncparks.gov/bryophytes/index.php), and it is one of two areas in the United States with the highest number of endemic moss species (meaning they live only in the Southern Appalachians and nowhere else; California is the other endemic hotspot). 

Places with abundant moss cover are indicative of healthy ecosystems, since their absence usually indicates something is wrong, like too much pollution or disturbance. The Fraser fir – red spruce forests at the top of Mt. Mitchell are home to many moss species which can serve as refugia for very small animals. For instance, tardigrades, which are primitive microscopic animals, live in these mosses (https://www.npca.org/articles/1067-the-mosses-at-our-feet), as does the endemic spruce-fir spider (Microhexura montivaga, the world’s smallest tarantula at only 1/8” long and which is extremely endangered; https://www.nwf.org/Magazines/National-Wildlife/2017/Oct-Nov/Conservation/Spruce-Fir-Moss-Spider). So, give the mosses a look-see the next time you’re wandering around these high elevation ecosystems.

This coming Saturday, September 23rd, at 2:49 am, is the fall equinox, when the length of the day equals the length of the night. It also marks the official end of summer and start of autumn. After this date, the days get shorter until we reach the winter solstice on December 21st at 9:47 pm, after which they will start to get longer.

Next week I’ll check out some other high elevation sites, including Grandfather Mt and the surrounding area. So far, its looking good for the upcoming fall color season. The weather has cooled off this week, which is something we need for bright, on-time colors, so let’s hope that continues. Until next week, wishing you the best.

Photos Week of September 17th