The Blue Oak is also known as the Iron Oak and Mountain White Oak. It is found on the western slopes of the Sierras up to 3000ft in dry areas.

This is one of the most widely distributed hardwood trees in California. It is one of the last to show its new leaves and when it does it is an explosion of chartreuse! This tree is an indicator species so it will tell us when something is going wrong in its ecosystem. There currently is a lack of regeneration of this species in the foothills. It is believed that fire is essential to its success and an increase is livestock and deer may be impacting new tree growth.

“Blue Oak compartmentalize injuries and will grow around foreign material. In the video an old fencepost on my property was enveloped by this Blue Oak tree. The image shows where a barbed wire fence was attached in 3 places and the tree enveloped the metal parts that were left on the tree.”

“Blue Oaks line my meandering commute to work everyday. I love watching them in the changing light, weather and seasons and as they thrive and succumb. In 2007 I was inspired to create this painting titled ‘Strength’ from photos I had taken of trees in this same area. I did not know they were Blue Oaks at the time but I feel the same sense of awe now as I did then.”

There are many cool critters that inhabit the leaves and branches of Oaks. The Oak galls above are created by a type of wasp. The galls start out yellow and turn black as they age. Ink is made from galls. It is called ‘gall ink’.

https://www.kqed.org/science/23927/what-gall-the-crazy-cribs-of-parasitic-wasps

Description:

• Size: small to medium-sized tree, 20-60 feet

• Bark: light gray and scaly

• Leaves: pale green above, even paler beneath. 1.25 to 4 inches long, .75 to 1.75 inches wide with 4-5 shallow round lobes. The leaf margins are mostly smooth, but may have fine, serrated edges.

• Fruit: slender acorn, .75 to 1.75 inches.

• Other: hairy twigs. Creeping, twisting, stretching branches. Will support a tire swing but at your own peril as the large branches can be hollow.