The Flora of the PCT
A9 Highway 78 to Highway S22 (Barrel Springs)
A9 Highway 78 to Highway S22 (Barrel Springs)
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| Fig. 1.
Top row. Left: Ocotillo in front of Scissors Crossing, where San Felipe Creek crosses SR78, with Granite Mountain in the background. Right: lace-fringed spineflower, Chorizanthe fimbriata var. laciniata. Middle row. Left: Desert community members at beginning of this segment: Mohave yucca, Yucca schidigera; Gander's cholla, Cylindropuntia ganderi; ocotillo, Fouquieria splendens; California juniper, Juniperus californica. Right: Typical segment of trail contouring around each and every side canyon, showing post-burn shrubs. Shaun Hawke is gazing at Granite Mountain in the background, probably remembering the times she's hiked and botanized the PCT there in the past. The PCT to the south contours around the west side (right side of photograph) of Granite Mountain. Bottom row. Left: California barrel cactus, Ferocactus cylindraceus. Right: closeup of lace-fringed spineflower, Chorizanthe fimbriata var. laciniata. Photos by RT Hawke taken on this segment of the PCT on 18 April 2014. Click on the pictures for larger versions. | |
| Segment | Segment Start | Segment End | Segment Length | Elevation (feet) | ||
|---|---|---|---|---|---|---|
| Min | Max | Range | ||||
| A9 | Highway 78 | Highway 22 | 24.0 miles | 2250 | 4420 | 2170 |
| Subsegments | ||||||
| A9a | Highway 78 | 4.2 miles from Highway 78 | 4.2 miles | 2250 | 3080 | 830 |
| A9ab | Highway 78 | High Point on PCT | 18.5 miles | 2250 | 4420 | 2170 |
| A9c | Highway S22 | High Point on PCT | 5.5 miles | 3450 | 4420 | 970 |
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This section covers roughly mile 78 to mile 102 from the Mexican Border (see notes on accuracy of mileages).
Topo! gives 22.9 miles for this segment. The PCT Data Book gives 23.9 miles. We've adopted 24.0 miles. The one-way hike from south to north has a total elevation gain of 2970 feet, and a total elevation loss of 1770 feet see the profile below. The one-way hike from north to south has a total elevation gain of 1770 feet, and a total elevation loss of 2970 feet. A round-trip hike of this section is 48.0 miles, with an elevation gain and loss of 4740 feet. We have broken up this section into three units. Section A9a is the first 4.2 miles of trail. Section A9b is the middle part of the trail, but since the easiest way to access this is from either end of the trail, we have included it with Section A9a as Section A9ab, which covers the first 18.5 miles of trail. Section A9c is the last 5.5 miles of trail, which we have done from Highway S22 south to the high point of the trail. | ||||||
Introduction
Survey Dates
The Plant Checklists
Introduction
This is a very long, dry section of trail, 24 miles from Highway 78 just east of Scissors Crossing to Highway S22 just past Barrel Springs.
But this is a fascinating segment botanically! This is the only part of the PCT that passes through an area with the classic signature plants of the Lower Colorado Desert vegetation, with species as ocotillo, Fouquieria splendens; California barrel cactus, Ferocactus cylindraceus; and teddy-bear cholla, Opuntia bigelovii (Figs. 1 and 2). In fact, this is one of the best places to observe California barrel cactus, accompanied here by Gander's cholla, Cylindropuntia ganderi; Engelmann's hedgehog cactus, Echinocereus engelmannii; and California fish-hook cactus, Mammillaria dioica.
Fig. 2. A dense stand of California barrel cactus, Ferocactus cylindraceus; accompanied by Gander's cholla, Cylindropuntia ganderi; desert agave, Agave deserti; and teddy-bear cholla, Opuntia bigelovii. This is the only section of the PCT with signature plants of the Lower Colorado Desert vegetation.
Photo by Tom Chester, taken on 6 January 2012 from the PCT just above Scissors Crossing.
Click on the picture for a full camera frame taken just to the left of this photograph, looking down to Scissors Crossing.
You may wonder how it is that the Pacific Crest Trail is passing through a low-elevation desert area. There are two reasons. First, the trail really should be located 10 miles to the west, following the crest of the Volcan Mountains, as mandated by the original Congressional authorization for the PCT. However, it was difficult to gain access to that area, which is mostly private property, so the Forest Service located the trail in mostly-public lands here.
Second, the area around Scissors Crossing, at the beginning of the segment, is the very westernmost extension of the Lower Colorado Desert vegetation here, thanks to the rain shadow of the Laguna Mountains, the low elevations around Scissors Crossing, and the south-facing slopes here.
Although the PCT crosses the Lower Colorado Desert again at Banning Pass, most of the signature plants of that desert are missing at that location.
The trail begins in open Borrego Desert vegetation, and gradually transitions to desert chaparral for most of its length. Just before the high point on the trail, chamise chaparral appears, which becomes dense past the high point (Fig. 3). The vegetation at the beginning and end of this segment is completely different (compare Figs. 2 and 3).
Fig. 3. Dense stand of chamise, Adenostoma fasciculatum, with only a few other species here and there.
Photo by Tom Chester, taken on 10 January 2015 from the PCT just north of the high point of this section, looking southwest.
Click on the picture for a larger version.
The first 1.5 miles of this segment climbs the slopes of the San Felipe Hills to reach an elevation of 3000 feet elevation. It then stays on the southwest slopes of the San Felipe Hills, between elevations of 3000 and 3600 feet, for the next 12 miles. Although on average the trail parallels the nearly-straight line Highway S2, northward progress on the trail is slow, since the trail weaves in and out of numerous side canyons along the way in order to stay nearly at a constant elevation for long stretches.
Near mile 13, the trail gets serious about gaining elevation, and crosses the ridgeline of the San Felipe Hills at mile 18.5. The trail then descends to Highway S22 on the northeast side of the ridgeline.
This area has experienced a number of fires in recent years. This is probably due to an introduced species, cheat grass, Bromus tectorum, that fills the spaces between shrubs and catches on fire easily when dried up, enabling fire to sweep through areas that normally would not burn so readily.
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Fig. 4. Left: Trail Map for the PCT Section A9 from Highway 78 to Highway S22, from USDA Forest Service Interactive Map.
Right: Elevation profile from Highway 78 to Highway S22, from south to north.
Click on the pictures for larger versions.
Survey Dates
The surveys of this section of trail, in time order, are:
- Section A9a, 13 December 2010; initial survey of trail for first 0.8 miles, by Tom Chester, with Mike Crouse for half the survey.
- Section A9a, 6 January 2012; survey of first 1.9 miles, by Tom Chester, Mike Crouse, and Kate Harper, with Steve Fuller for part of the survey.
- Section A9a, 10 January 2012: survey of first 2.4 miles, by Tom Chester, Mike Crouse, and Kate Harper.
- Section A9a, 18 March 2013: survey of first 1.9 miles (plus exploring up a side drainage), Tom Chester, Adrienne Ballwey, Mike Crouse, and Kate Harper.
- Section A9c, 30 March 2013: high point on trail to Highway S22 (Barrel Springs), 5.5 miles, surveyed by RT and Shaun Hawke. 112 species observed, very beginning of flowering season. Years before, a fire had turned the area in a riot of wildflowers. The post-fire blooms are now gone, and the chaparral and oak woodland vegetation have returned.
- Section A9abc, 18 April 2014: Scissors Crossing to fallen gate, 23.5 miles, surveyed by RT and Shaun Hawke.
- Section A9c, 27 April 2014: Barrel Springs to fallen gate, 0.7 miles, surveyed by RT and Shaun Hawke.
- Section A9c, 5 February 2015: 1.0 miles surveyed by Tom Chester, Adrienne Ballwey, James Dillane, Jim Roberts, and Steve Fuller
- Section A9c, 10 February 2015: 5.2 miles, surveyed by Tom Chester, Adrienne Ballwey, Keir Morse, and Steve Fuller
- Section A9a, 25 March 2015: 5.2 miles, surveyed by Tom Chester, Adrienne Ballwey, Kate Harper, Carla Hoegen, and Fred Melgert.
- Section A9c, 30 March 2015: 2.9 miles, surveyed by Tom Chester, Adrienne Ballwey, Nancy Accola, Kate Harper, and Tom Sommers.
The Plant Checklists
There are usually four different versions of the Plant Checklists, which differ depending on:
- whether only species observed in the immediate vicinity of the trail are included, or whether species are also included from the larger area surrounding the trail, some of which might be found on the trail in future surveys;
- whether the list is presented in trail order, or in plant family order; and
- whether thumbnail photographs are included with the list or instead, links are provided to Calphotos pix and the Jepson Manual eflora.
We have broken up this section into three units. Section A9a is the first 4.2 miles of trail. Section A9b is the middle part of the trail, but since the easiest way to access this is from either end of the trail, we have included it with Section A9a as Section A9ab, which covers the first 18.5 miles of trail. Section A9c is the last 5.5 miles of trail, which we have done from Highway S22 south to the high point of the trail.
Because there are only 16 species found in Section A9b that are not found in Section A9a, we give only the lists for Section A9ab. The additional 16 species are numbered 181 to 222 in the trail order list, and so are easily identified there and ignored if one wants a list only for Section A9a. The family order list retains the number from the trail order list, so those species again can easily be ignored if one wants only the A9a family order flora.
The entire Section A9
- Illustrated Family Order List from Calflora, with two thumbnail pictures for every species found on the trail. (372 taxa). Note the checkbox at right that allows a sort of the list in family order instead of scientific name order, or a sort by bloom start month. Check Show photo service links and then click on Display to get links to all Calphotos et al pictures.
- Species in Order Along the Trail, from Highway 78 to Highway S22 (Barrel Springs), with links to Jepson Manual Treatment and Calphotos (not given since we have not recorded the species in section A9c in this order; use the species order list for Section A9ab to get all but the last 5.5 miles)
- Species Seen on or near the Trail in a Family Order List, with links to Jepson Manual Treatment and Calphotos (372 taxa)
- Species Seen on or near the Trail, along with species vouchered from this general area, in a Family Order List, with links to Jepson Manual Treatment and Calphotos. (not given since this is the same as the preceding list).
Only Section A9a and Section A9ab
- Illustrated Family Order List from Calflora, from Highway 78 to the high point on the trail, with two thumbnail pictures for every species found on the trail. (254 taxa). Note the checkbox at right (under the Format link) that allows a sort of the list in family order instead of scientific name order, or a sort by bloom start month. Check Show photo service links and then click on Display to get links to all Calphotos et al pictures.
- Species in Order Along the Trail, from Highway 78 to Highway S22 (Barrel Springs), with links to Jepson Manual Treatment and Calphotos (222 observed taxa plus 32 vouchered or nearby taxa; total of 254 taxa).
- Species Seen on or near the Trail in a Family Order List, with links to Jepson Manual Treatment and Calphotos (Since there are few species not found on the trail in Section A9a, we made only the next list.)
- Species Seen on or near the Trail, along with species vouchered from this general area, in a Family Order List, with links to Jepson Manual Treatment and Calphotos. (254 taxa).
Only Section A9c
- Illustrated Family Order List from Calflora for Highway S22 (Barrel Springs) to High Point on PCT Section A9 (204 taxa). Note the checkbox at right that allows a sort of the list in family order instead of scientific name order, or a sort by bloom start month. Check Show photo service links and then click on Display to get links to all Calphotos et al pictures.
- Species in Order Along the Trail, from Highway S22 (Barrel Springs) to High Point on PCT Section A9 (north to south), with links to Jepson Manual Treatment and Calphotos. (205 taxa).
- Species Seen on or near the Trail in a Family Order List, with links to Jepson Manual Treatment and Calphotos (205 taxa)
- Species Seen on or near the Trail, along with species vouchered from this general area, from , in a Family Order List, with links to Jepson Manual Treatment and Calphotos. (List is same as the previous one, since the only vouchers for this section were from the vicinity of the trail.).
Separate condensed print versions of just the checklist names are available for all except for the Calflora thumbnail picture version, as a link on each of those pages.