Agave shawii
Encyclopedia
Agave shawii, occasionally called Shaw's Agave is an agave
found only along the Pacific coast of Baja California
, extending north into the coastal chaparral
of southernmost California
.
It is a small-to-medium agave, with green ovate leaves 20-50 cm long and 8-20 cm wide, and a variable pattern of marginal teeth. The inflorescence
forms a panicle
2-4 meters in height, whose 8-14 lateral umbel
s are subtended by large purple bract
s. Each umbel consists of a mass of yellowish or reddish flowers.
It generally flowers February to May, and as typical for agaves, the rosette dies thereafter. Although capable of reproducing by suckering, populations vary considerably in their behavior, with some consisting entirely of individual rosettes, while others form groups or colonies of clones.
Subspecies goldmaniana is generally larger, with longer (40-70 cm) lanceolate leaves, and 18-25 umbels on a 3-5 meter stem, and predominates in the desert of the central peninsula.
Although occasionally cultivated, this agave is frost tender, with damage starting at -5 degrees C and becoming extensive at -8 degrees. Plants in containers have been able to survive 18 degrees F with no damage located on the Central Coast. Frost cloth has also allowed plants to survive well with temperatures well below freezing for long periods (days) without damage. Plants enjoy a sandy loam soil that has good drainage. Roots are very rapid responders to rain and dry plants have been documented to start growing feeder (rain) roots within 3 hours after exposure to the rain. Plants are subjected to mealybug attack and systemic treatments should be used regularly. Plants develop best color when exposed to full sun along the coast. Some relief from the hot afternoon sun in the inland valleys would provide the best results for growers. A slow growing plant, the young may take 5 years to reach a good 2 gallon container size. Plants bloom from 30 years old on, with prolific pupping prior to dying post flowering. Seeds are best sown fresh with no stratification required. A great landscape plant that should enjoy more popularity when larger numbers make the plant more readily available. Very few nurseries are growing this plant.
The remaining population within California that is confirmed as naturally occurring located near Border Field State Park was destroyed by the Federal Government using the Department of Homeland Security's national security policy that allowed the destruction in order to construct the triple fence designed to prevent immigrants coming over the border from Mexico. Local native plant ethusiasts and nurserymen acted quickly to remove and rescue as many of the plants that could be saved within a very limited timeframe. Plans are to reestablish the population post development with the wild collected plants. There is another listed population located at Cabrillo National Monument. There is much speculationas to whether this is a relict
population or what planted there are some time in the past. Genetic studies have not been conducted to determine if the population is related to either the Border Field population or those farther south. The geographic separation of the two populations is approximately 15 miles.
Agave
Agave is a genus of monocots. The plants are perennial, but each rosette flowers once and then dies ; they are commonly known as the century plant....
found only along the Pacific coast of Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
, extending north into the coastal chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
of southernmost California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
.
It is a small-to-medium agave, with green ovate leaves 20-50 cm long and 8-20 cm wide, and a variable pattern of marginal teeth. The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
forms a panicle
Panicle
A panicle is a compound raceme, a loose, much-branched indeterminate inflorescence with pedicellate flowers attached along the secondary branches; in other words, a branched cluster of flowers in which the branches are racemes....
2-4 meters in height, whose 8-14 lateral umbel
Umbel
An umbel is an inflorescence which consists of a number of short flower stalks which are equal in length and spread from a common point, somewhat like umbrella ribs....
s are subtended by large purple bract
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
s. Each umbel consists of a mass of yellowish or reddish flowers.
It generally flowers February to May, and as typical for agaves, the rosette dies thereafter. Although capable of reproducing by suckering, populations vary considerably in their behavior, with some consisting entirely of individual rosettes, while others form groups or colonies of clones.
Subspecies goldmaniana is generally larger, with longer (40-70 cm) lanceolate leaves, and 18-25 umbels on a 3-5 meter stem, and predominates in the desert of the central peninsula.
Although occasionally cultivated, this agave is frost tender, with damage starting at -5 degrees C and becoming extensive at -8 degrees. Plants in containers have been able to survive 18 degrees F with no damage located on the Central Coast. Frost cloth has also allowed plants to survive well with temperatures well below freezing for long periods (days) without damage. Plants enjoy a sandy loam soil that has good drainage. Roots are very rapid responders to rain and dry plants have been documented to start growing feeder (rain) roots within 3 hours after exposure to the rain. Plants are subjected to mealybug attack and systemic treatments should be used regularly. Plants develop best color when exposed to full sun along the coast. Some relief from the hot afternoon sun in the inland valleys would provide the best results for growers. A slow growing plant, the young may take 5 years to reach a good 2 gallon container size. Plants bloom from 30 years old on, with prolific pupping prior to dying post flowering. Seeds are best sown fresh with no stratification required. A great landscape plant that should enjoy more popularity when larger numbers make the plant more readily available. Very few nurseries are growing this plant.
The remaining population within California that is confirmed as naturally occurring located near Border Field State Park was destroyed by the Federal Government using the Department of Homeland Security's national security policy that allowed the destruction in order to construct the triple fence designed to prevent immigrants coming over the border from Mexico. Local native plant ethusiasts and nurserymen acted quickly to remove and rescue as many of the plants that could be saved within a very limited timeframe. Plans are to reestablish the population post development with the wild collected plants. There is another listed population located at Cabrillo National Monument. There is much speculationas to whether this is a relict
Relict
A relict is a surviving remnant of a natural phenomenon.* In biology a relict is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas....
population or what planted there are some time in the past. Genetic studies have not been conducted to determine if the population is related to either the Border Field population or those farther south. The geographic separation of the two populations is approximately 15 miles.