Plant Guide to Nighthawk Loop Trail, Santa Rosa Plateau

This is a working list, about which we make no guarantees at all until we officially release it. Use at your own risk!

This trail is incomplete for annuals only noticeable in the spring since it has not been covered during spring.

Introduction and Explanation of Plant Trail Guides

Highlights of This Trail
Fieldwork Dates and Summary of List Changes With Time
The Plant Guide
Comments On Specific Species


This is a 0.6 mile round-trip loop hike beginning and ending at the Sylvan Meadows Parking Lot, with ~50 feet of elevation gain and loss.

Highlights of This Trail

The botanical highlights of this trail are:

Number of Unique Taxa On This Trail

The following histogram gives the number of trails in our database that contain each taxon on this trail. There were 90 trails in our database when this histogram was made; 16 of those trails, including this one, are at the Santa Rosa Plateau Ecological Reserve. A number of "1" means the taxon has only been found only on this list, among all the trails in our database; numbers of "16" or smaller may indicate taxa found only in this area.

Number of Trails
Containing A Taxon
Number Of Taxa
On This Trail
% of Taxa
On This Trail

We found 3 additional species not in the above table, since they have not been fully identified yet. The unidentified ones are marked with ? or sp in the id? column in the guide, and have no entries in the #all column.

Fieldwork Dates and Summary of List Changes With Time

The following table gives the dates the trail was walked and taxa recorded. After each visit, the table gives the total number of taxa on the list and the breakdown of the taxa without positive identification. See Explanation of Plant Trail Guides to understand the symbols below.

Visit DateVisit ## taxa# "?"# "sp"# "~"# "ssp"

The beginning 0.01 miles was also covered on 2/2/06.

The Plant Guide

Version for printing, without lines and other text on this page: html (3 pages), pdf Clickbook booklet (1 double-sided page), or Large Type pdf Clickbook booklet (2 double-sided pages). (See printing instructions for an explanation of these options)

The mileages are within 0.05 miles of a GPS measurement of the entire route, but the GPS measurement was only accurate to about that value. Hence the raw pedometer readings have not been adjusted. They should have an absolute accuracy of ~0.05 miles and a relative accuracy of ~0.01-0.02 miles.

Miles#id?Common NameLatin Name#here#all
0.00   Begin trail on east side of Sylvan Meadows Parking Area at opening in fence; elevation ~1870 feet (570 m)
0.00l  Sign: "Nighthawk Loop Trail 0.6 mi"
0.00b1ssp*foxtail barleyHordeum murinum20 / 2 
0.00b2 *soft chessBromus hordeaceus99 / 940
0.00l3spneedlegrassNassella sp. /  
0.00r4 *ripgut bromeBromus diandrus10 / 252
0.00b5 *slender wild oatsAvena barbata99 / 940
0.00l6~*knotweedPolygonum arenastrum5 / 119
0.00r7 *sand spurreySpergularia bocconei5 / 114
0.00r8 Engelmann oakQuercus engelmannii10 / 923
0.00   l: Display board; iron ranger "Pay Fees Here"; r: picnic tables
0.00l9 rusty-haired popcorn flowerPlagiobothrys nothofulvus+ / 13
0.00l10~*short-fruited filareeErodium brachycarpum99 / 914
0.00l11 *redstem filareeErodium cicutarium / 55
0.00l12 *narrowleaf filagoFilago gallica99 / 945
0.01   Y-Jct to begin the loop; go right
0.01r13sspfiddleneckAmsinckia menziesii50 / 5 
0.01r14 Spanish cloverLotus purshianus var. purshianus99 / 931
0.01r15 dove weedEremocarpus setigerus50 / 924
0.01b16 rattlesnake weedDaucus pusillus50 / 929
0.01r  (coast-range melic, Melica imperfecta)
0.01b17 checkerbloomSidalcea malviflora ssp. sparsifolia50 / 925
0.01r18 dwarf lupineLupinus bicolor10 / 329
0.02r19 purple clarkiaClarkia purpurea ssp. quadrivulnera99 / 926
0.02r20 *Australian bromeBromus arenarius99 / 93
0.02b21 Pomona locoweedAstragalus pomonensis20 / 911
0.02r22 *red bromeBromus madritensis ssp. rubens / 53
0.02r23 San Diego birdsfoot lotusLotus hamatus / 24
0.03l  (horseweed, Conyza canadensis)
0.03r24 Indian milkweedAsclepias eriocarpa30 / 918
0.04l  (telegraph weed, Heterotheca grandiflora)
0.04b25 *prickly sow thistleSonchus asper ssp. asper2 / 230
0.05r26 common bedstrawGalium aparine / 41
0.05r27 southern miner's lettuceClaytonia perfoliata ssp. mexicana99 / 925
0.07b28 *prickly lettuceLactuca serriola99 / 942
0.07b29 graceful tarplantHolocarpha virgata ssp. elongata99 / 914
0.08r30 *smooth cat's earHypochaeris glabra99 / 935
0.09b31 western ragweedAmbrosia psilostachya10 / 137
0.09r32 *sow thistleSonchus oleraceus / 42
0.10r33 *nit grassGastridium ventricosum / 25
0.10r34 toad rushJuncus bufonius var. bufonius10 / 114
0.10r35 clustered toad rushJuncus bufonius var. congestus10 / 17
0.10r36 *curly dockRumex crispus1 / 123
0.11l37 horseweedConyza canadensis1 / 136
0.11r  (poison oak, Toxicodendron diversilobum)
0.12r38 miner's lettuceClaytonia perfoliata ssp. perfoliata / 22
0.13r  (yellow salsify, Tragopogon dubius)
0.15r  nodding needlegrassNassella cernua+ / 17
0.16r  (leafy daisy, Erigeron foliosus var. foliosus)
0.17r  (Vertical slabs of rock; fragrant everlasting, Gnaphalium canescens ssp. beneolens; California everlasting, Gnaphalium californicum)
0.19l39 sharp-toothed sanicleSanicula arguta / 16
0.19l40 *shortpod mustardHirschfeldia incana20 / 551
0.20r41 purple needlegrassNassella pulchra / 20
0.21b42 Palmer's goldenbushEricameria palmeri var. pachylepis10 / 310
0.22l43 California-asterLessingia filaginifolia var. filaginifolia20 / 751
0.23l44 California squirreltailElymus elymoides ssp. californicus / 9
0.24r45 long-stemmed buckwheatEriogonum elongatum var. elongatum20 / 328
0.24r  (California fuchsia, Epilobium canum ssp. canum)
0.24r  Jct. use connector trail to Motrero Trail
0.24r  (common lomatium, Lomatium utriculatum)
0.25r  Jct. official connector trail to Motrero Trail; trail begins long curve to left
0.26l  (coast live oak, Quercus agrifolia var. agrifolia)
0.29r  Bench with back, in memory of Ken Jacobs / Frank Gray, with a great quotation on it
0.29r46 California fuchsiaEpilobium canum ssp. canum5 / 121
0.29r47 lanceleaf dudleyaDudleya lanceolata5 / 120
0.29   Switchback left; near low point on trail, elevation 1840 feet (561 m)
0.33r48 purple sanicleSanicula bipinnatifida1 / 111
0.33r49 *California burcloverMedicago polymorpha5 / 140
0.33r50 *scarlet pimpernelAnagallis arvensis5 / 133
0.33l51 *goldentopLamarckia aurea5 / 122
0.35   Cross dike made of what looks like melted Bedford Canyon formation
0.36l52spstrigose lotus?Lotus strigosus? /  
0.39l53 *wild oatsAvena fatua5 / 126
0.40l54 *common chickweedStellaria media20 / 125
0.40l55 *hedge parsleyTorilis nodosa10 / 114
0.40l56 coast live oakQuercus agrifolia var. agrifolia1 / 143
0.42l  Bench with back
0.43l57 silver puffsUropappus lindleyi1 / 126
0.44l58 blue wildryeElymus glaucus ssp. glaucus3 / 121
0.44l  (California peony, Paeonia californica)
0.46b59 *tocaloteCentaurea melitensis5 / 145
0.46r  (bird's-foot fern, Pellaea mucronata var. mucronata)
0.46r60 leafy daisyErigeron foliosus var. foliosus1 / 144
0.46b61 blue dicksDichelostemma capitatum ssp. capitatum / 46
0.47r62 branching phaceliaPhacelia ramosissima var. latifolia2 / 234
0.47l63 goldenrodSolidago californica5 / 135
0.47r  Bench with back; view of small waterfall in season in drainage straight ahead
0.48r  (California bee plant, Scrophularia californica ssp. floribunda; purple head, Acourtia microcephala; basketbush, Rhus trilobata)
0.50   Cross shallow drainage
0.53r  (climbing bedstraw, Galium nuttallii ssp. nuttallii)
0.55   Jct. beginning of loop; end guide
0.56   Back at trailhead

Comments On Specific Species

Plagiobothrys nothofulvus. The id for the specimen at mile 0.00 comes from a specimen at mile 0.05.

Nassella cernua. This taxon is not numbered unless the previous Nassella sp. turns out to be a different taxon than N. cernua.

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Copyright © 2004-2006 by Tom Chester and Kay Madore
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 4 April 2006.