In 2018 I decided to pursue a goal I had had for many years, and that was to select a single trail or area, and revisit it many times over the course of a single season. We had a very good rainfall event in the foothills of the San Gabriels early in the year that germinated a lot of annuals, and the cool weather extended into June which prolonged the blooming season. Since my home is only a few blocks from the base of the Mt. Wilson Trail, I decided to do that. The Mt. Wilson Trail is a terrific trail, 7.5 miles from the bottom to the top at Mt. Wilson, and with a 4500' elevational differential has tremendous diversity. Over the course of the year I compiled a list of approximately 250 species which I had observed, identified and photographed. Tom Chester provided a list he had made in 2005 for the first quarter of the trail, and some additional possibilities from a voucher search of the area, and I made about 20 visits to various sections of the trail, either beginning at the bottom in Sierra Madre, or at the top. This was in addition to the more than 30 visits I had made in previous years. So far in January 2019 I have already been on the trail three times. The trail is divided approximately into four sections, bottom to First Water, First Water to Orchard Camp, Orchard Camp to Manzanita Ridge, and Manzanita Ridge to the parking lot at the top. I plan to continue my exploration of the flora on this trail for the near future.

The Mt. Wilson Trail was originally created by Benjamin ("Don Benito") Wilson in 1864 no doubt based on faint footpaths utilized by the Gabrielino Indians. His goal in building this trail was to acquire timber from the mountaintop. In 1889 the trail was used to laboriously carry the Harvard University telescope up to the first observatory on top of Mt. Wilson. Don Benito built a construction camp halfway up the trail at what is now called Orchard Camp. What he referred to as his 'Halfway House' was later homesteaded by two Georges, George Aiken and George Islip, who planted an extensive grove of apple, cherry, plum and chestnut trees. In 1890 Orchard Camp was turned into a trail resort by James McNally which flourished and was immensely popular over the following five decades. In 1911 40,000 people signed the register at the camp. The trail resort was abandoned in 1940 and today is just a sylvan glen. Most people hike as far as First Water and turn around but there are those that hike to the top and back on a weekly basis.

Going over lists of species vouchered on or near the trail, there are clearly numerous species that have been either correctly or incorrectly identified since the beginning of the last century, and others that may have been located in nearby areas, but this gallery only includes those taxa that have been seen on the trail itself. There are still questions in my mind about certain taxa such as the oaks and the grasses in particular, and I am hoping that Tom Chester will be able to help me fill in some of these blanks. Toward the beginning of the trail there are a number of species that are clearly escapes from nearby residential areas, and I include them here simply because people might notice them and wonder what they are. The gallery includes a couple of adjacent minor trails such as the new high loop trail below First Water and the trail that goes up the canyon from First Water to the rope. This gallery is organized alphabetically by genus.

I would certainly be remiss were I not to acknowledge the generous and significant help of Tom Chester and I thank him for it. An asterisk next to the common name indicates a non-native species, and the symbol ~ is for a taxon that needs to be confirmed.