Acacias in bloom at UC Davis Arboretum

One local spectacle I made a point of not missing this year is the acacia bloom at the Eric E. Conn Acacia Grove at the UC Davis Arboretum. From the Arboretum website:

The Eric E. Conn Acacia Grove displays over 50 species of acacias from Australia, Africa, and the Americas. In early spring, visitors can walk through clouds of fragrant yellow blossoms amid meadows of native California bunchgrasses. We are testing these attractive heat- and drought-tolerant plants, which range from prostrate, low-growing species to tall shade trees, for use in Central Valley gardens. The grove is named for Dr. Eric E. Conn, professor emeritus of biochemistry at UC Davis and an internationally-recognized expert on acacias.

Apparently many tender species from the Americas and Africa have died over the years so today the collection is heaviest on Australian species (see taxonomical note at the bottom).

Eric E. Conn Acacia Grove in early March

Ovens wattle (Acacia pravissima)

Ovens wattle (Acacia pravissima)

According to the docent who led a walk through the Acacia Grove in early March, American and African acacias are closest to the mimosas from which they are thought to have originated. Their leaves still look like the typical mimosa leaves while many Australian species have evolved in a different direction, with leaves that are often radically different from the typical mimosa leaf. In fact, many Australian species, such as the popular Acacia pravissima, have phyllodes (modified flat leaf-like structures that are actually modified stems) instead of traditional leaves.

Ovens wattle (Acacia pravissima)

In Australia, acacias are commonly called “wattles.” When I hear the word “wattle” I think of the fleshy protuberances hanging from the neck of a rooster, but in reference to acacias the word comes from wattle and daub, a traditional building method that goes back thousands of year.

Hairy wattle (Acacia vestita)

Whatever you prefer to call them, I find acacias to be beautiful year round. But in February and March they are impossible to beat when it comes to sheer visual impact. An acacia at the peak of its bloom is like a yellow beacon you can see from half a mile away. Check out the photos below, and you’ll agree.

Hairy wattle (Acacia vestita)

Hairy wattle (Acacia vestita)

Hairy wattle (Acacia vestita)

Hairy wattle (Acacia vestita)

Knife-leaf wattle (Acacia cultriformis)

Knife-leaf wattle (Acacia cultriformis)

Knife-leaf wattle (Acacia cultriformis)

West Wyalong wattle (Acacia cardiophylla)

 

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Queensland silver wattle or pearl acacia (Acacia podalyriifolia)

Shoestring acacia (Acacia stenophylla)

Silver wattle (Acacia dealbata)

Silver wattle (Acacia dealbata)

Silver wattle (Acacia dealbata)

Silver wattle (Acacia dealbata)

Nealie (Acacia rigens)

Nealie (Acacia rigens)

Wilhelm’s wattle (Acacia wilhelmiana)

Wilhelm’s wattle (Acacia wilhelmiana)

Snowy River wattle (Acacia boormanii)

Snowy River wattle (Acacia boormanii)

Snowy River wattle (Acacia boormanii)

Snowy River wattle (Acacia boormanii)

Acacia redolens ‘Desert Carpet’

Bank catclaw (Acacia redolens ‘Desert Carpet’)

Bank catclaw (Acacia redolens ‘Desert Carpet’)

Bank catclaw (Acacia redolens ‘Desert Carpet’) and Wilhelm’s wattle (Acacia wilhelmiana)

Coast wattle (Acacia longifolia var. sophorae)

Blue bush (Acacia covenyi)

Blue bush (Acacia covenyi)

Blue bush (Acacia covenyi)

Brisbane golden wattle (Acacia fimbriata)

Brisbane golden wattle (Acacia fimbriata)

Brisbane golden wattle (Acacia fimbriata)

Sweet acacia (Acacia farnesiana ‘Sierra Sweet’), one of the few American acacias in the collection. Its leaves are very mimosa-like.

Sweet acacia (Acacia farnesiana ‘Sierra Sweet’) with flower buds

 

Taxonomical side note courtesy of Wikipedia:

The genus Acacia previously contained roughly 1,300 species, about 960 of them native to Australia, with the remainder spread around the tropical to warm-temperate regions of both hemispheres, including Europe, Africa, southern Asia, and the Americas (see List of Acacia species). However, in 2005, the genus was divided into five separate genera under the tribe "Acacieae". The genus Acacia (sensu stricto) was retained for the majority of the Australian species and a few in tropical Asia, Madagascar, and Pacific Islands. Most of the species outside Australia, and a small number of Australian species, were reclassified into Vachellia and Senegalia. The two final genera, Acaciella and Mariosousa, each contains about a dozen species from the Americas.