Common Oak (Quercus calliprinos)

Arabic name: بلوط

The Common Oak (Quercus calliprinos), is a dominant plant in the Eastern Mediterranean region, forming dense scrub on dry hillsides.  It is native to Jordan, where it grows in Ajlun, Jerash, Salt, Amman, Tafila, and Shobak.  Unfortunately, Oak forests are threatened with cutting, and overgrazing. 

This evergreen tree can grow to a height of 10m, with a spread of 8m, and has slow growth of less than 25cm per year.  Although slow growing, Quercus calliprinos may live up to 700 years.  Also, it is tolerant of harsh conditions, and regenerates quickly after fires.  It also re-sprouts after cutting to the ground or grazing.

Requirements:
Common Oak grows in full sun, and is drought-tolerant.  It colonizes poor ground of dry limestone, and siliceous soils. 

Water usage:
Common Oak requires no watering once established.  Generally, trees need supplemental irrigation to get established, especially if planted after the rainy season.  During the first year, irrigate in the amount of 20 – 25 liters of water twice a week. During its second year, a tree needs to be irrigated in the amount of 40 liters once a week.  Beginning with the third year, trees usually get established, and some, like the Common Oak, do not require any supplemental irrigation. 

Appearance:
The Common Oak tree usually grows with a single stem when protected.  Leaves are 2 – 3cm long, oblong, leathery, and have spiny margins.  Quercus calliprinos can be distinguished from other oaks by the velvety undersides of the otherwise similar dark green spiny leaves.  Flowers are not showy; they are arranged in 4 –5cm long clusters that bloom from March to April, and fall soon after.  Fruits are 1 – 3cm long, narrow acorns that are nearly covered by caps with distinctive pointed outgrowths.  The tree has far-reaching roots.

When fenced and allowed to grow, its leaves gradually lose their defensive features, and the branches reach out.  

Notes on use:
Distinguished by its dense shade; good along roads and for reforestation.  This evergreen species also is adaptable as a hedge, screen or windbreak.  In addition, it can serve as a dominant focal point in the garden.

Propagation:
Small quantities of seed can be sown in deep pots in a cold frame.  Plants produce a deep taproot and need to be planted out in their permanent positions as soon as possible.  In fact, seed sown in-situ will produce the best trees.  Trees should not be left in a nursery bed for more than two growing seasons without being moved or they will transplant very badly.

Intolerant of root disturbance, trees should be planted in their permanent positions whilst young.  Any transplanting should be done once growth has commenced in late May.

Comments:
The flowers and fruit of Oak Trees provide sustenance for many kinds of wildlife.

This article is part of a series of articles prepared by the Center for the Study of the Built Environment (CSBE) on water conserving landscapes. 

For additional information on water conserving gardens, visit the CSBE web site at www.csbe.org

Support for the CSBE project on water conserving landscapes is provided by WEPIA (Water Efficiency and Public Information for Action), a program being implemented in collaboration with the Ministry of Water and Irrigation and funded by the United