Plant Notes From Car Trip Between Fallbrook and Anza-Borrego State Park
The purpose of this trip was to search for leafy common rabbitbrush, Chrysothamnus nauseosus ssp. consimilis. I've found a number of specimens of Chrysothamnus nauseosus ssp. bernardinus which key out perfectly to consimilis, even though it is quite unlikely that this is their id. Hence I wanted to locate some definite consimilis for comparison.
I hoped to locate some consimilis at The Narrows, a location mentioned in Beauchamp's Flora of San Diego County, and expected to see some in the mountains bordering the desert. I was quite surprised not to find any rabbitbrush at all anyplace. It looked like rabbitbrush has been replaced by Encelia along most of the route, with a few locations having Isocoma.
This page documents the route I took, since it is often just as interesting to note where a species was not observed as where it is observed. I give the identity of all the potential rabbitbrush plants along the way, along with a few other plant notes.
On the first portion of the trip, I noticed that white everlasting, Gnaphalium canescens microcephalum in bloom was obvious even at 45 mph. So I decided to also sample it occasionally to see if I could find fragrant everlasting, Gnaphalium canescens beneolens. I was successful at doing that.
The trip was on Sunday, September 21, 2003, from ~11 a.m. to ~4 p.m. It is of course possible that rabbitbrush may have been present, but not blooming. However, I did recognize the only occurrence of Ericameria pinifolia by observing and recognizing plants that were not blooming, from my car at 40 mph. This bush has a very similar shape to the rabbitbrush that I have seen. Hence if rabbitbrush had been present in any quantity, I most likely would have found it.
All coordinates are from a GPS receiver, and hence the altitude could be off by 100 feet or so. The mileage is measured from the intersection of SR76 and I-15. I drove an extra 0.8 mile to get to stop 2, since I had to backtrack after seeing the Isocoma bush. I also drove into the San Luis Rey Picnic Area, which added a bit of mileage. The Mile Marker along the road is abbreviated MM in the table.
The locations are plotted using Topo! at Level 1 and Level 2, using the levels defined by the program.
Stop # Mile Latitude Longitude Elevation (feet) Location Description Comments 1 19.2 33.29760 -116.91902 2258 SR76 Gnaphalium canescens microcephalum (GCM): lvs not decurrent; faint smell; upper cauline lvs spreading 2 26.6 33.27500 -116.83528 2336 SR76 Ericameria parishii - a very healthy bush! MM 43.0 3 30.1 33.25389 -116.79222 2541 SR76 - San Luis Rey picnic area. The river was flowing strongly. 4 42.4 33.23611 -116.65139 2993 S22 (Lessingia glandulifera or Pectis papposa), Ambrosia acanthicarpa, California aster, telegraph weed, California buckwheat, Stephanomeria exigua 5 46.3 33.21833 -116.59278 3396 S22 Begin burn area. Gnaphalium canescens beneolens!! Upper cauline lvs appressed, ~fragrant, lvs look decurrent, but don't appear to be when I pull them off in the field. But they did at home. Heads very compact, floriferous. 6 48.3 33.21278 -116.56000 3695 S22 Ericameria pinifolia - only beginning ~0.5 mile back, and no more the rest of the trip. 7 55.3 33.21750 -116.45111 3179 S22, now in Anza-Borrego State Park Huge honking what looks like nude buckwheat! Encelia farinosa in full bloom; probably Amaranthus fimbriatus, Tribulus terristris, cholla, California buckwheat. Gold patches visible, probably due to Pectis papposa. 8 57.9 33.21278 -116.42278 2364 S22 Parking area with one spanish needles, Palafoxia arida, in bloom; Encelia farinosa, Bebbia juncea, and probably Boerhavia coulteri. 9 70.0 33.21056 -116.32722 515 Borrego Springs Road just past Yaqui Pass Road, at La Casa del Zorro Arundo donax. 10 75.4 33.16389 -116.25361 613 Borrego Springs Road, Texas Dip, Sal Felipa Wash Desert willow, Chilopsis linearis ssp. arcuata, in full bloom. 11 80.1 33.13083 -116.30083 1024 SR78, The Narrows Earth Trail Hiked around looking for rabbitbrush, for 0.33 miles on the trail and then in the wash on the north side of SR78. Full bloom: Burro-weed, Ambrosia dumosa; Amaranthus fimbriatus; Bouteloua aristidoides^2 everywhere. Some bloom: chuparosa, Justicia californica. Old flower stalks: big galleta, pleuraphis rigida. 12 89.3 33.11472 -116.44167 1975 SR78, middle of Sentenac Canyon Isocoma acradenia bracteosa beginning about a half mile earlier; common reed, Phragmites australis. 13 91.6 33.09833 -116.47083 2227 SR78, Scissors Crossing Isocoma acradenia still. 14 33.06639 -116.55278 2666 SR78, Banner Canyon near Banner Beginning of burn area near Banner about a half mile before. 15 99.1 33.08139 -116.57111 3189 SR78, middle of Banner Canyon A single (goldenbush?) about a half mile back, unreachable from the road.
Copyright © 2003-2004 by Tom Chester.
Permission is freely granted to reproduce any or all of this page as long as credit is given to us at this source:
Comments and feedback: Tom Chester
Updated 14 November 2005.