Wednesday, March 30, 2016

Wednesday, March 23, 2016

Bird’s Eye Gilia

Tricolor Gilia

Bird's Eye Gilia: photo by Cliff Hutson
Bird's Eye Gilia: photo by Cliff Hutson

Bird’s Eye Gilia, or Tricolor Gilia, (Gilia tricolor) is an annual herb that is native to California, where it is found naturally in the Central Valley and surrounding mountain ranges and foothills, with major populations around the Bay Area. 

A member of the Phlox family (Polemoniaceae), it is described as delicate with a spreading branched stem that grows up to a foot in height. The leaves are alternate and finely dissected. It may bloom from April through August. One would think, given the name, that the, 1/2 inch wide or wider flowers, borne atop the stems, would have three colors. White and lavender are predominate in the petals. One then has a choice of the blue pollen or one of the throat colors of yellow and dark purple for the third. One source cites the “blue stamens encircling the yellow throat of the flower, which is set off by a dark purple ring”.  The flowers seem very attractive to bees. Humans can only imagine what they are seeing at their short-wavelength end of the spectrum of visible light.

The Gilia genus, as previously noted, is named for Filippo Luigi Gilii (1756-1821), naturalist and director of the Vatican observatory.  He, for twenty-one years, made twice daily meteorological readings at the Observatory, and had the meridian line and obelisk placed in front of St. Peter's for readings of the seasons.

This gilia is widely cultivated, being frequently included in wildflower seed mixes. In addition to bees, it attracts butterflies and birds. It is drought-tolerant; suitable for xeriscaping, and does not mind full sun. My research found  herbaria with two specimens that were collected well outside its range.  One was from Silverado Canyon in Orange County. The other from “Claremont; North side of Foothill Blvd. between Darthmouth (sic) and College Ave.” As the latter is just out side the grounds of the botanic garden where I work, I am willing to bet that these specimens were garden escapees. 

Wednesday, March 16, 2016

Globe Gilia

Gilia capitata

Globe Gilia: photo by Cliff Hutson
Globe Gilia: photo by Cliff Hutson

Gilia capitata, a member of the phlox family (Polemoniaceae) is an annual herb that is native to California that is also found outside of California, but confined to western North America. Common names for it are Blue Field, Blue-headed, and Globe Gilia.

Globe gilia is an annual which can bloom from April to July with 25 to 100 small blue five-lobe flowers per round head. The stamens protrude slightly from the flower's mouth and can be white with white, blue, or pink anthers. Its leaves are finely dissected in to small linear lobes on stems - sometimes having glandular hairs - which can grow to a height of anywhere from 10 to 90 centimeters. Couple that variability with the fact that there are eight subspecies with differences in the degree of hairiness and the size and shape of the individual flowers, and you have the makings for some interesting discussions out in the field.

That field would most commonly be in a sandy or rocky area below 7,000 feet throughout most of the state. And, here again, the variability crops up as this could be in any of the Mixed Evergreen Forest, Douglas-Fir Forest, Yellow Pine Forest, Northern Coastal Scrub, Coastal Prairie, Red Fir Forest, Foothill Woodland, Coastal Strand, Coastal Sage Scrub, or Chaparral communities.

The binomial name is also open to discussion.  Capitata simply refers to the way the flowers form in a head-like cluster. But, Gilia is after Filippo Luigi Gilii (1756-1821) an Italian naturalist.  Thus, some say, its pronunciation should follow the Italian rule which makes a 'g' before 'i' soft. Also in Italian the 'i' is pronounced as 'ee,' so in order to preserve the pronunciation of the original name, Gilia should properly be said as 'JEE-lee-uh." But, it seems the Spanish pronunciation is more commonly heard.

Wednesday, March 9, 2016

Joshua Tree

Joshua Tree: photo by Cliff Hutson
Joshua Tree: photo by Cliff Hutson

Yucca brevifolia, the Joshua tree, is a plant native to California; indeed it is the signature plant of the Mojave Desert.  It is also found in western Arizona, southern Nevada, and southwestern Utah.

A member of the “century plant” family, Agavaceae, it is not truly a tree. But, its size - between 15-40 feet in height,with a diameter of 1-3 feet - makes it seem like one.They grow 2 to 3 inches a year, take 50 to 60 years to mature and they can live up to 150 years. One interesting characteristic is that the evergreen leaves live for about a year, then hang on to form a brownish thatch around the branches. Flowers may appear from February to late April.

Each species of yucca has a specific moth that pollinates it. In this case it is the Joshua tree yucca month (Tegeticula synthetica). The moth is the tree’s only pollinator. The tree is the only food the moth’s larvae eat. An example of mutualism; the tree and the month share the task of making more trees and more moths.  

However, these plants face a problem in that the primary disperser of their seeds has not been around for about 11,000 years. The Shasta ground sloth is believed to have played this important role. Clearly the trees are still with us, but it has been proposed that the lack of these sloths helping to spread the seeds to more favorable climates is causing the trees to decline. It has been further suggested that, if climate change continues on its present course, the Joshua tree will eventually no longer grow in its namesake national park. 

Joshua Tree National Park: photo by Cliff Hutson
Joshua Tree National Park: photo by Cliff Hutson

Wednesday, March 2, 2016