Goldenbush

Isocoma menziesii

Overview

 
Overview
In the fall, much of the flower color in the Reserve is provided by goldenbush (coastal goldenbush or Menzies' goldenbush, Isocoma menziesii), a low shrub frequently found along the trails and in dry, open areas. Because the bloom peak occurs after that of most flowers, goldenbush is important as a nectar source for insects and a hunting ground for predatory spiders and insects.
 
                                         

Description


Description 2,4,26,43,59

 

Goldenbush is a rounded, shrubby perennial, usually less than 4 feet (1.5m) tall, although specimens around the Nature Center are taller. Several main stems arise from a woody base.

 

Leaves are usually less than 2 inches (5 cm) long, obovate, often clustered along the stem; margins range from smooth to coarsely toothed. Leaves are resinous and color varies from gray-green to green. Leaves and stems may have scattered white hairs.

 

Flower heads consist of 6-50 yellow disk florets clustered together at the ends of branches. A two-branched yellow stigma protrudes beyond the petals, the ends curling, often appearing as a loop. The receptacle has 3-6 rows of small, overlapping leaf-like phyllaries that “shingle” the base. These expand outward at the tip and bear a tiny spine.  The major bloom time is April - December.1 but a few scattered flowers may be found all year.

 

Seeds are tan cylinders, 5/64-10/64 inches (2-4 mm) long, with a terminal cluster of yellow-tan bristles (the pappus) about twice the length of the seed.

 

               

Other Common Names: 
Coastal goldenbush, Menzies' goldenbush

Distribution

Distribution 7,8,34

Goldenbush is native to California and western North America. Our variety, vernonioides, is centered in central and southern California and Baja, below 4000 feet (1200 m). It is one of the dominant species in coastal sage scrub and is also found in chaparral, and in wetlands.
 
Goldenbush is widely distributed in the Reserve and is easily found along the trails in all three basins.
 
 
           
This plant occurs primarily in the following vegetation types in the San Elijo Lagoon Ecological Reserve: 
Chaparral
Coastal sage scrub
Coastal strand

Classification

Classification

Goldenbush is a dicot angiosperm in the sunflower family, Asteraceae.2,11 This is the largest family of vascular plants in the Northern Hemisphere.143 “Flowers” of Asteraceae are made up of one or both of two types of flowers: symmetrical disk florets and strapped-shaped ray florets. These are crowded onto a common base (receptacle), and together are often assumed to be a single flower, which is called a flower head.44,49 

Other familiar Asteraceae that occur in the Reserve include California sagebrush (Artemisia californica), bush sunflower (Encelia californica), and telegraph weed (Heterotheca grandiflora).

Species in the genus Isocoma have only disk flowers and a pappus of brownish, silky hairs. There is only one species of Isocoma in the Reserve,48 but the related genus Hazardia contains two species (H. squarosa and H. orcuttii) which occur in smaller numbers in the Reserve and which may be confused with goldenbush.

Goldenbush is a variable species with several recognized varieties. Although only one variety, vernonioides, has been reported from the Reserve,48 other varieties or hybrids may occur.1

 

          

 

Alternate scientific name(s): 
Isocoma veneta, Haplopappus venetus

Ecology

Ecology

Although goldenbush occurs primarily in the coastal sage scrub, the leaf characteristics are more similar to those of chaparral species;39 they are small, tough, resinous and evergreen, all adaptations that reduce water loss. Goldenbush also has a well developed root system to facilitate water uptake.43 Unlike many species of the coastal sage scrub, goldenbush does not resprout readily after a fire.43

 

                  

Human Uses

Human Uses  

In spite of its abundance, goldenbush does not seem to have been used by native Americans.43 It is not widely used for native gardens, although we have seen it used effectively for fall color in at least one local garden.79 Seeds are often included in seed mixes for revegetation and erosion control.43
 
              

Interesting Facts

Interesting Facts

Like most of the fall blooming plants in the Reserve, oastal goldenbush is an important resource for insects and insect-predators.59
 
This species is named after Archibald Menzies who accompanied Captain Vancouver in the Discovery on a voyage around the world.21 Menzies was charged with investigating the whole of the natural history of the countries visited, enumerating all trees, shrubs, plants, grasses, ferns and mosses by their scientific names as well as the language of the natives, and determining whether plants introduced into Europe were likely to thrive.
 
 
                

 

Photos

Central Basin, south side (Rios trailhead); Sept. 2013
East Basin, south side (Santa Carina trailhead); Sept. 2007
East Basin, south side (Santa Carina trailhead); Sept. 2007
Central Basin, south side (Rios trailhead); Sept. 2009
Central Basin, south side (Rios trailhead); Sept. 2009
Nature Center; July 2009
Nature Center; Aug. 2009
Central Basin, south side (Rios trailhead); Sept. 2013
Nature Center; Aug. 2009
Nature Center; July 2009
green lynx spider; Nature Center; Aug. 2009
green lynx spider with prey; East Basin, south side (weir); Aug. 2011
Central Basin, south side (Rios trailhead); Oct. 2011
Central Basin, south side (Rios trailhead); Oct 2011
praying mantis; East Basin, south side (Santa Carina trailhead); Sept. 2013
East Basin, south side (Santa Carina trailhead); Sept. 2013
East Basin, south side (Santa Inez trailhead); Nov. 2012
Central Basin, south side (Rios trailhead); Sept. 2013
East Basin, south side (Santa Carina trailhead); Sept. 2013
East Basin, south side (Santa Carina trailhead); Sept. 2013
East Basin, south side (Santa Inez trailhead); Nov. 2012
East Basin, south side (Santa Carina trailhead); Sept. 2013
Central Basin, south side (Rios trailhead); Oct. 2010; photo courtesy of Barbara Wallach
Central Basin, south side (Rios trailhead); Dec. 2010; photo courtesy of Barbara Wallach
Central Basin, south side (Rios trailhead); Oct. 2010; photo courtesy of Barbara Wallach
Central Basin, south side (Rios trailhead); Oct. 2010; photo courtesy of Barbara Wallach
Central Basin, south side (Rios trailhead); Oct. 2010; photo courtesy of Barbara Wallach
April 2007; photo courtesy of Dense Stillinger
Central BAsin, south side (Rios trailhead); Dec, 2017; photo courtesy of Mark Jenne