Ceanothus cordulatus is a species of shrub in the family Rhamnaceae known by the common names mountain whitethorn and whitethorn ceanothus. It is native to California and adjacent sections of Oregon, Nevada, and Baja California, where it grows on mountain ridges and other forested areas. This is a spreading shrub growing usually wider than tall and up to about 1.5 meters. The stems are gray, with the twigs yellow-green in color and fuzzy in texture when new. The evergreen leaves are alternately arranged and up to 3 centimeters long. Each is oval in shape with three ribs and generally not toothed. The leaves may be hairy or not. The inflorescence is panicle-shaped, up to about 4 centimeters long. The flowers are white to off-white with five sepals and five petals. The fruit is a rough, ridged capsule up to half a centimeter long. It has three valves inside, each containing a seed. It is a nitrogen-fixing plant, that is uniquely abundant in old-growth forest conditions when compared to similar types of nitrogen-fixing plants. In addition, Ceanothus cordulatus is known to be an important source of nitrogen patches for significantly longer times than other similar post-disturbance successional shrubs, following disturbance events such as forest fires.
No narrative description available for this taxon yet.
⚠ sources differ — GIFT: 2.4 m · USDA: 1.98 m · TRY: 2.44 m
Seed mass3.65 mg
⚠ sources differ — TRY: 3.65 mg · GIFT: 3.23 mg
Seed mass max5.3 mg
Seed mass min2.12 mg
Life cycle & reproduction25
Bloom periodEarly Summer
Coppice potentialNo
Deciduousnessevergreen
Dispersal typeunspecialized
Flower colourwhite
Flower conspicuousYes
Fruit seed period beginSummer
Fruit seed period endFall
Growth rate USDASlow
Life formshrub
Life spanperennial
Lifespan categoryLong
Propagated by bare rootYes
Propagated by bulbNo
Propagated by containerYes
Propagated by cormNo
Propagated by cuttingsNo
Propagated by seedYes
Propagated by sodNo
Propagated by sprigsNo
Propagated by tubersNo
Resprout abilityYes
Seed spread rateModerate
Seedling vigorLow
Vegetative spread rateNone
Habitat & environment22
Active growth periodSpring and Summer
Adapted to coarse textured soilsYes
Adapted to fine textured soilsNo
Adapted to medium textured soilsYes
BloatNone
Climatetemperate
Climberself-supporting
Foliage colorGreen
Foliage porosity summerDense
Foliage porosity winterModerate
Foliage textureFine
Fruit colourbrown
Growth formtree
Growth form USDAMultiple Stem
Hedge toleranceHigh
Known allelopathNo
Leaf retentionNo
Low growing grassNo
Root depth min20 in
Shape and orientationSemi-Erect
Small grainNo
Woodinesswoody
Physiology & chemistry22
Anaerobic toleranceNone
C:N ratioLow
Caco3 toleranceHigh
Cold stratification requiredNo
Drought toleranceHigh
Fertility requirementLow
Fire resistantNo
Fire toleranceHigh
Frost free days min112 days
Leaf p1.7 mg/g
Moisture useLow
Nitrogen fixation levelLow
Photosynthetic pathwayC3
Precipitation max53 in
Precipitation min16 in
Protein potentialLow
Salinity toleranceLow
Shade toleranceHigh
Soil pH max8.4 pH
Soil pH min6.65 pH
Temperature min-23 °F
Wood density528 mg/cm³
Uses & economy15
Berry nut seed productNo
Christmas tree productNo
Commercial availabilityField Collections Only
Fodder productNo
Lumber productNo
Naval store productNo
Nursery stock productNo
Palatable browse animalHigh
Palatable graze animalLow
Palatable humanNo
Post productNo
Pulpwood productNo
Seeds per pound166 000 per lb
ToxicityNone
Veneer productNo
Other traits7
Fall conspicuousNo
Fruit seed abundanceHigh
Fruit seed conspicuousNo
Fruit seed persistenceNo
Height at 20yr1.37 m
Planting density max3 764 per acre
Planting density min691 per acre
05DNA & barcoding3 specimens
A DNA barcode is a short, standardised stretch of genes that works like a fingerprint — enough to tell one species from another. Below is the molecular trace Ceanothus cordulatus has left across the world's sequence archives.
At a glance
DNA specimens3
Marker genes4
GenBank sequences4
eDNA detections3
Countries1
The DNA barcodea real sequence read deposited for this species
★ the standard DNA barcode for this group — the short region actually read to tell this species apart. The rest are extra genes sequenced along the way.
★matK1★rbcL1★ITS2★ITS2
plant barcodefungal barcode
07Deep time~1.98 Ma lineage
How far back this lineage goes — and how we know. Everything here is measured in Ma, short for “mega-annum”: millions of years ago. The chart reads left to right like a calendar of the Earth, from the deep past on the left to today at the right edgetop to bottom like a core drilled through the Earth, from the deep past at the top down to today at the bottom.
At a glance
DNA clock origin1.98 Ma TimeTree
When this lineage existed
How to read this: the coloured strip along the bottomdown the left is the geological calendar — the standard epochs (Pliocene, Pleistocene…) every museum uses, shown so you can see which chapter of Earth's history this lineage lived in. This lineage is a young one, so the strip is zoomed in to epochs — the finer subdivisions inside a period. The orange marker is the DNA clock: DNA accumulates mutations at a roughly steady rate, so comparing this species' DNA with its relatives estimates when the lineage split off — independently of any fossil.
DNA clock origin
08Occurrence & distribution
Record type3 375 records
Wild obs. + sensor2 474
Museum / vouchered899
Fossil1
Other1
Origin
Native120
Range
Area of Occupancy AOO5 796 km²
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
Coordinate accuracy90% within 1 km
≤100 m 1 413≤1 km 216≤10 km 136>10 km 55
1 820 georeferenced · 654 without coordinates
Open the mapobservation + sensor2 474
Museum / Voucheredphysical evidence
Backed by a physical specimen — a herbarium sheet, sample or voucher held in a collection. “Vouchered” means supported by material evidence, not just an observation.
Coordinate accuracy58% within 1 km
≤100 m 57≤1 km 274≤10 km 228>10 km 15
574 georeferenced · 325 without coordinates
Open the institutions mapphysical evidence899
Wildobservation + sensor
Human sightings and records, or camera-trap / sensor detections — someone (or a device) saw or captured the species in the wild.
10Collections & institutions
Holding institutions44 of 58 geolocated
Institutions and collections holding physical, vouchered specimens of this species — click a row to fly to it on the map.
Institution
Specimens
Claremont, US
159
Riverside, US
70
CASlocation not on record
68
Davis, US
62
San Diego, US
51
Santa Barbara, US
48
Arcata, US
36
Angwin, US
32
Corvallis, US
28
DOI/NPS, Little Rock Central High School National Historic Sitelocation not on record
23
Los Angeles, US
18
San Luis Obispo, US
17
US
14
Ensenada, MX
12
Severin-McDaniel Insect Collectionlocation not on record
9
Canadian Department of Agriculturelocation not on record
9
Bronx, US
8
Northridge, US
6
San Jose, US
6
Wuzhou, CN
4
Fullerton, US
4
EL PASO, US
4
DOI/NPS, Greenbelt Parklocation not on record
4
Long Beach, US
4
ASUlocation not on record
4
Tempe, US
4
San Francisco, US
3
Truckee, US
3
Vancouver, CA
2
Mexico City, MX
2
Logan, US
2
Austin, US
2
St. Paul, US
2
Henderson, US
2
Bangkok, TH
2
Austin, US
2
Mexico City, MX
2
University of Stellenboschlocation not on record
2
Bloomington, US
2
Phoenix, US
2
Philadelphia, US
1
Fort Bragg, US
1
Chongqing Museumlocation not on record
1
Christchurch, NZ
1
La Paz, MX
1
Moscow, US
1
Pomona Collegelocation not on record
1
MeiseBGlocation not on record
1
Santa Cruz, US
1
Saint Louis, US
1
Chadron, US
1
Wellington, NZ
1
WTUlocation not on record
1
STNFlocation not on record
1
Boise, US
1
Arizona State University Biocollectionslocation not on record
1
Bureau of Land Management, Medford District Officelocation not on record
1
Pullman, US
1
58 institutions · 752 of 899 vouchered records shown · 147 without an institution code
09Environmental DNA3 detections
Where the DNA of Ceanothus cordulatus was picked up in samples of water, soil or air — nobody saw the organism, only its DNA left behind. A trace is a clue that the species was near, not a confirmed sighting.
Signal
Detections DNA found3
Studies independent surveys1
Signal confidence: weakweighed across independent studies, places & mapped detections
Where its DNA was found
0 of 3 detections have coordinates
Open the map0 countries0
How strong is each trace?
DNA read depthRead counts were not reported for this species — the map shows presence only, not how strong each trace was.
How to read this: each dot is one detection of this species' DNA in an environmental sample. The confidence meter weighs how many independent studies and places back up the signal — one detection in one study is a hint; many across several studies is solid. Records dated before 2008 (when eDNA methods began) are treated as likely mislabeled and left off the map.
WikipediaWikimedia Foundation2 languages↗
BioWikiNetmultilingual Wikipediamultilingual↗
GBIFGlobal Biodiversity Information Facility3 375 records↗
ENAEuropean Nucleotide Archive · EMBL-EBI3 eDNA detections↗
BOLD SystemsCentre for Biodiversity Genomics3 specimens↗
NCBIUS National Library of Medicinesequences↗
GRIN TaxonomyUSDA-ARSdistribution & uses↗
Open Tree of LifeOpenTreephylogeny backbone↗
GLoBIGlobal Biotic Interactionsbiotic interactions↗