Understanding Autumn Color in Colorado
By: Gary Gray
This shot was taken on September 24th, 2007. The vantage point is from the Red Mountain Mine looking down at the Million Dollar Highway towards Ouray with Mount Abrams in the background. I'm at about 10,000 feet when I snap this photo. The color you are looking at is mostly above 9000 feet here. Lower down the hill, it is still green.
I've been photographing the Autumn Color in Colorado for years and here's a quick take on what I've learned.
Defining "Peak Color" can result in a number of definitions. To me, Peak Color in the mountains is when most of the leaves have changed below 10,000 feet and are still on the trees. Once the leaves are coming off the trees at any altitude, we're beyond peak. If you are planning on doing photography in the mountains, you need to figure out when the peak color is going to be occurring at the altitude where you'll be working and plan your trip accordingly. For anything 8-10 K feet, I'd say the 1st week of October is going to be the overall best time to plan a trip.
1st rule. Don't read the news channel predictions. They aren't really any more accurate with their color predictions than you would be by dead reckoning that color is about to change. They do give pretty good reports on where the good color is, but they don't seem to mention the altitude. Don't fool yourself into thinking things are any different this year than previous years with when changes happened. They always make the same mistake and account for color change by latitude rather than altitude, claiming that color changes are earlier in the northern mountains than in the southern mountains. There may be a tiny difference, but it has more to do with altitude and weather than if it is north or south. Autumn color change starts in Anchorage, Alaska around the same time it starts in Colorado. Other dynamics are far more important.
As a general rule of thumb, you can pretty much say October 1st is going to be close to peak color on average for anything above 8500 feet in altitude. Rocky Mountain National Park, Elk Mountains, Mt. Evans, Georgetown, Bailey, and The San Juan Mountains are going to be coming into peak color at high altitude at this time. This color can vary a bit from area to area, for reasons I haven't quite figured out. An example of this variation would be the town of Granby, which always seems to be about 1-2 weeks ahead of everywhere else. Other areas are slower and not all places are the same. Remember, I'm speaking on average here. A quick drive through the mountains with a GPS that indicates your altitude will confirm where the color is changing.
You can calculate the rate of change in a general sense at being approximately 1,000 feet per week. Meaning, if today, April 22nd, color above 10,000 feet was peaking, one week from now, color above 9000 feet will probably be peaking, and two weeks from now color above 8000 feet will probably be peaking, so on and so forth...
Another example. Telluride, Colorado. A popular Autumn photography destination. The city is at 8,700 feet. If the weather is mild, you can expect the color in Telluride itself to be peaking between October 1st and the 10th. In the mountains above Telluride at higher altitudes, the color has already changed and the leaves may have already blown off the trees. My typical approach is to get there early, not late. Late means you get there and the leaves are gone. Early means you get there and the leaves are on but half of them are still green. You'll actually only have about a 4-5 day window max at any given altitude before the highest color point and loss of foliage begins. It is just too unpredictable at high altitude and those winds are gong to strip those trees every time they blow. Your job, catch that window.
The real issue is how well and how long the leaves will hold their color for any given altitude and how long they will stay on the trees. I've seen the color peak above 9000 feet and the leaves be totally gone above 10,000 feet and be totally green below 8500 feet.
Denver is always going to have a Mid-October Peak. Figure it out, we're at 5,800 feet here. If mountain peak is end of Sept-October 1st above 8000 feet, you'll see color peaking at 5-6 thousand feet about 2-3 weeks after that.