Jepson eFlora: Taxon page
Vascular Plants of California
Key to families | Table of families and genera
Previous taxon Index to accepted names and synonyms:
| A | B | C | D | E | F | G | H | I | J | K | L | M |
| N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Next taxon

Philadelphus microphyllus


Higher Taxonomy
Family: HydrangeaceaeView DescriptionDichotomous Key
Habit: Perennial herb to small tree or vine. Stem: < 3 m, generally erect; bark generally peeling as thin sheets or narrow strips. Leaf: generally simple, opposite, deciduous or not, +- hairy; stipules 0; blade +- round to narrowly elliptic, entire or toothed. Inflorescence: cyme, raceme, panicle, or flower 1, terminal or axillary, generally bracted. Flower: bisexual, radial, flowers on inflorescence margins occasionally sterile and enlarged; sepals 4--10, free or fused at base, spreading or erect; petals 4--7, free, +- round to narrowly elliptic; stamens 8--12 in 2 whorls or many and clustered, filament base linear or wide and flat; pistil 1, ovary superior to inferior, chambers 2--8, ovules 1--2 or many per chamber, placentas axile or parietal, styles 1--8, free or fused at base. Fruit: capsule, loculicidal or septicidal; styles persistent or not. Seed: generally many, small to minute, oblong to fusiform, winged or not.
Genera In Family: 18 genera, +- 250 species: generally temperate, subtropical northern hemisphere; some cultivated for ornament (Carpenteria, Hydrangea, Philadelphus). Note: Philadelphaceae in TJM (1993).
eFlora Treatment Author: Robert E. Preston & Charles F. Quibell
Scientific Editor: Douglas H. Goldman, Bruce G. Baldwin.
Genus: PhiladelphusView DescriptionDichotomous Key

Common Name: MOCK ORANGE
Habit: Shrub < 3 m. Stem: bark red-brown, aging gray, peeling as narrow rectangles or strips; twigs glabrous to hairy. Leaf: deciduous, petioled; blade 3-veined from base, +- glabrous to hairy, margin entire to toothed. Inflorescence: flower 1, or raceme to panicle, terminal, +- open. Flower: fragrant; sepals 4--5, glabrous to hairy; petals 4--5, white; stamens generally many, clustered, filaments linear, fused at base; ovary 1/2 to completely inferior, chambers 4--5, placentas axile, ovules many, style 1, branches generally 4, stigmas linear along style branches. Fruit: becoming woody, generally loculicidal. Seed: many, generally fusiform, generally brown.
Etymology: (Greek: for Ptolemy Philadelphus, Greek king of Egypt, 309--247 BC) Note: Many intergrading infraspecific taxa described; more study needed to determine which warrant recognition.
Reference: Frazier 1999 New Mexico Botanist 13:1--6
Unabridged Reference: Hitchcock 1943 Madroño 7:35--56; Hu 1956 J Arnold Arbor 37:15--90
Philadelphus microphyllus A. Gray
Leaf: petiole 5--18 mm; blade 3--8 mm wide, narrowly ovate to elliptic, margin entire, +- rolled under. Flower: sepals 3--5 mm, petals 6--8 mm, widely elliptic.
Ecology: Rocky slopes, cliffs, pinyon/juniper woodland; Elevation: 1340--3350 m. Bioregional Distribution: e PR (SnJt, Santa Rosa Mtns), W&I, e DMtns; Distribution Outside California: to Texas, northern Mexico. Flowering Time: May--Jul
Synonyms: Philadelphus microphyllus var. stramineus (Rydb.) Henrickson; Philadelphus microphyllus subsp. pumilus (Rydb.) C.L. Hitchc.; Philadelphus microphyllus var. pumilus (Rydb.) Henrickson; Philadelphus microphyllus subsp. stramineus (Rydb.) C.L. Hitchc.; Philadelphus pumilus Rydb.; Philadelphus stramineus Rydb.
Jepson eFlora Author: Robert E. Preston & Charles F. Quibell
Reference: Frazier 1999 New Mexico Botanist 13:1--6
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

Previous taxon: Philadelphus lewisii
Next taxon: Whipplea

Botanical illustration including Philadelphus microphyllusbotanical illustration including Philadelphus microphyllus

Please use this Google Form for Contact/Feedback

Citation for this treatment: Robert E. Preston & Charles F. Quibell 2012, Philadelphus microphyllus, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on July 12, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora,, accessed on July 12, 2024.

Philadelphus microphyllus
click for image enlargement
©2015 Steve Matson
Philadelphus microphyllus
click for image enlargement
©2015 Steve Matson
Philadelphus microphyllus
click for image enlargement
©2015 Steve Matson
Philadelphus microphyllus
click for image enlargement
©2015 Steve Matson
Philadelphus microphyllus
click for image enlargement
©2015 Steve Matson

More photos of Philadelphus microphyllus
in CalPhotos

Geographic subdivisions for Philadelphus microphyllus:
e PR (SnJt, Santa Rosa Mtns), W&I, e DMtns
1. You can change the display of the base map layer control box in the upper right-hand corner.
2. County and Jepson Region polygons can be turned off and on using the check boxes.
map of distribution 1

(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurrence).


Data provided by the participants of the  Consortium of California Herbaria.

View all CCH records
All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.

CCH collections by month Flowering-Fruiting Monthly Counts

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).