Ceanothus cordulatus

The seeds of Ceanothus cordulatus can self-disperse by forcibly ejecting from the seed pods when they ripen.  The seeds are highly dependent on fire for germination. Leaves and the soil around this species are high in nitrogen due to the presence of Frankia, a nitrogen-fixing bacteria that associates with its roots.
Photo Credit: © Eric in SF via Wikimedia Commons
Ceanothus cordulatus
Common Name: whitethorn ceanothus
Plant Functional Group: Evergreen broadleaf
Class > Order > Family: Magnoliopsida > Rosales > Rhamnaceae
What does the species look like?

This evergreen shrub grows up to 1.5 meters tall and is spiny at the tips of the branches. Older bark is greyish-white, and younger twigs are yellow-green. The oval leaves are up to 3 centimeters long, have three ribs, and are sometimes hairy. The small white flowers have 5 petals and are found in clusters at the end of branches. The rough ridged fruit is 0.5 centimeters long and has three valves, each containing one seed.

Ceanothus cordulatus is found on rocky ridges and in open pine forests at elevations between 900 and 2900 meters.
 
Where is the species found?
States & Provinces
CA, NV, OR
Which phenophases should I observe?
Do you see...?
Leaves Young leaves
One or more young, unfolded leaves are visible on the plant. A leaf is considered "young" and "unfolded" once its entire length has emerged from a breaking bud, stem node or growing stem tip, so that the leaf base is visible at its point of attachment to the leaf stalk (petiole) or stem, but before the leaf has reached full size or turned the darker green color or tougher texture of mature leaves on the plant. Do not include fully dried or dead leaves.

How many young leaves are present?

  • Less than 3
  • 3 to 10
  • 11 to 100
  • 101 to 1,000
  • 1,001 to 10,000
  • More than 10,000
Flowers Flowers or flower buds
One or more fresh open or unopened flowers or flower buds are visible on the plant. Include flower buds or inflorescences that are swelling or expanding, but do not include those that are tightly closed and not actively growing (dormant). Also do not include wilted or dried flowers.
More...

How many flowers and flower buds are present? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), simply estimate the number of flower heads, spikes or catkins and not the number of individual flowers.

  • Less than 3
  • 3 to 10
  • 11 to 100
  • 101 to 1,000
  • 1,001 to 10,000
  • More than 10,000
Open flowers
One or more open, fresh flowers are visible on the plant. Flowers are considered "open" when the reproductive parts (male stamens or female pistils) are visible between or within unfolded or open flower parts (petals, floral tubes or sepals). Do not include wilted or dried flowers.
More...

What percentage of all fresh flowers (buds plus unopened plus open) on the plant are open? For species in which individual flowers are clustered in flower heads, spikes or catkins (inflorescences), estimate the percentage of all individual flowers that are open.

  • Less than 5%
  • 5-24%
  • 25-49%
  • 50-74%
  • 75-94%
  • 95% or more
Fruits Fruits
One or more fruits are visible on the plant. For Ceanothus cordulatus, the fruit is a three-lobed capsule that changes from green to reddish-green to dark brown, becomes slightly sticky, and splits open to expose the seeds. Do not include empty capsules that have already dropped all of their seeds.
More...

How many fruits are present?

  • Less than 3
  • 3 to 10
  • 11 to 100
  • 101 to 1,000
  • 1,001 to 10,000
  • More than 10,000
Ripe fruits
One or more ripe fruits are visible on the plant. For Ceanothus cordulatus, a fruit is considered ripe when it has turned dark brown and has split open to expose the seeds. Do not include empty capsules that have already dropped all of their seeds.
More...

What percentage of all fruits (unripe plus ripe) on the plant are ripe?

  • Less than 5%
  • 5-24%
  • 25-49%
  • 50-74%
  • 75-94%
  • 95% or more
Recent fruit or seed drop
One or more mature fruits or seeds have dropped or been removed from the plant since your last visit. Do not include obviously immature fruits that have dropped before ripening, such as in a heavy rain or wind, or empty fruits that had long ago dropped all of their seeds but remained on the plant.
More...

How many mature fruits have dropped seeds or have completely dropped or been removed from the plant since your last visit?

  • Less than 3
  • 3 to 10
  • 11 to 100
  • 101 to 1,000
  • 1,001 to 10,000
  • More than 10,000
What do these phenophases look like?

There is currently no photoguide available for this species. If you'd like help us create one, use the guidance document and species template provided here. Then send it via email to education@usanpn.org when it is complete.

USDA PLANTS profile for whitethorn ceanothus (USDA Symbol: CECO )