Cedrus spp
Mount Lebanon was once covered by a great forest where Cedar of Lebanon gains its name. These trees were used for timber by many ancient civilizations. The tree features in many ancient mythologies and religious texts e.g. the Bible, the Epic of Gilgamesh, and the Iliad. Cedar wood is aromatic, absorbs moisture, repels insects and inhibits rot/molds, so widely used for construction, and food storage where refrigeration is not available. The oil is used in herbal medicine, perfumes, and soaps.
- Culture
- Concerns
- Management
Culture for Cedar
There are three commonly cultivated species of Cedar: C. deodar, C. lebani, and C. atlantica. C. atlantica 'Glauca' has waxy blue leaves. These large trees, which can reach over 12m tall by 8m wide in 20 to 50 years, requires a significant amount of space. Requires full sun and well drained soil. Cedars require minimal pruning.
Concerns about Cedar
Sirococcus is a recently emerged disease. It causes dieback of shoots with needles initially turning pink, infect shoots may have a bent 'shepherd's crook' shape. The fungus then spreads into the branches and trunk forming dark bleeding lesions on the bark; these cankers may ultimately girdle and kill the tree. Also susceptible to Honey Fungus. Aphids are a significant insect pest. Mature cedars are prone to branch drop, posing a health and safety risk, this may be caused by heavy rain following a long dry period (e.g. drought) or by loading from heavy snow.
Management Practices for Cedar
Monitor for Sirococcus. Remove infected and destroy material/needles, sterilizing pruning tools. Applications of phosphites and foliar fertilisers may be of benefit. If Honey Fungus is present on site, ensure the tree is unstressed, remove any sources of infection. Buried root collars should be excavated. Check for aphids (curling leaves and honeydew). A treatment plan of 3 to 4 sprays at regular intervals throughout the active growing season should be used. Avoid applying horticultural oil to blue cedars, as this will ruin their colour.