Quercus douglasii is an endemic California oak tree, affectionately called “the blue oak”.

Given its rugged beauty and hardiness, Quercus rugosa is recommended for gardens, parks, and arboreta in most regions. As it grows naturally in such an extended area and across a variety of habitats and altitudes, there is also scope for further experimentation with seed sourced from different provenances.

Quercus semecarpifolia, commonly known as brown oak, is the main forest-forming evergreen tree species from upper temperate to subalpine regions (2,500–3,300 m) in Western Himalaya.

As we celebrate 25 years of the IOS, we take a look at oaks that have an association with silver. In a Species Spotlight Joeri Strijk describes Quercus argentata (the epithet derives from the Latin word for silver: argentum) and below are three well-known cultivars with silver associations.