Atlas cedar

Family

Pinaceae

Habit

Tree

Height

30 m

Spread

8 m

Growth

slow

Lifespan

250 years

First yield

after 25 years

Hardiness

zone 6–9

Shade tolerance

light shade

Soil

Sand, Silt, Loam

Soil moisture

dry – very moist

pH

6 – 7.5

Synonyms

Atlaszeder

Medicinal: An essential oil extracted from distilled branches serves as a potent antiseptic and fungicide, stimulating the circulatory and respiratory systems while calming the nerves. It also possesses astringent, diuretic, expectorant, and soothing properties. When diluted with a carrier oil like almond oil and massaged into the skin, it is utilized in treating skin conditions, ulcers, chest infections, catarrh, cystitis, and dandruff. It is employed as an inhalant for bronchitis, tuberculosis, and nervous tension. An infusion of the branches can also be beneficial.

Other uses: Essential oil distilled from branches is utilized in perfumery, particularly in jasmine-scented soaps, and also serves as an insect repellent. Plants can be grown as tall hedges, with fragrant and durable wood valued for carpentry, veneer, and construction purposes. Additionally, it is used in the production of insect-repellent items for textile storage.

Site: In central Europe the Atlas cedar reaches 25 to 40 metres and, with age, spreads just as wide, its horizontal branches layered like tiers of parasols. This is a tree for parks, avenues and large properties, not for a domestic garden, and it needs that room from the start, because crowding by neighbouring trees leaves it with a permanently one-sided crown. It is markedly heat- and drought-tolerant and is therefore regarded as a hope for a warming climate, with trial plantings under way in Bavaria and Baden-Württemberg. Waterlogging, by contrast, it will not take, and on heavy, compacted ground it stays stunted. As an evergreen conifer it casts deep shade year-round, under which little grows. Care: For the first three to five years it is distinctly more frost-sensitive than later and needs winter protection at the base in harsh positions; the blue-needled form 'Glauca' is considered the hardiest. Stake it initially, as young cedars are top-heavy. It is essentially never pruned: like all cedars it does not resprout from old, needleless wood, so cutting back leaves permanent holes. Keep a single leader and remove forks early. The wide horizontal branches are prone to snow breakage, so check them after wet snowfall. Under sustained climate stress it responds with resin flow and premature needle drop, already documented across large areas of its native range.

The Atlas cedar is raised from seed. The upright, barrel-shaped cones take two to three years to ripen and then disintegrate on the tree rather than falling whole, so the winged seeds trickle out individually; harvest therefore comes shortly before they break up. The seed is resinous and loses viability quickly, so it should be sown the same winter. Three to four weeks of cold stratification in moist sand is enough, after which it germinates promptly and without fuss. Seedlings are prone to damping off and need a free-draining, lean substrate. The tree does not become capable of flowering until 25 to 30 years old. Garden forms such as 'Glauca' and the weeping 'Glauca Pendula' do not come true from seed and are grafted onto seedling rootstocks.

The Atlas cedar is wind-pollinated and yields neither nectar nor any bee forage worth the name; unusually, it flowers in autumn, while most conifers shed pollen in spring. As a non-native it has no specialised insects in central Europe. Its value is structural: as a large evergreen with dense, horizontal tiers of branches it offers cover, windbreak and lookout perches all year, and holds nests at a time when broadleaved trees stand bare; woodpigeons, crows and raptors use such crowns regularly. The resinous seeds are taken by hawfinches and tits. In its native range in the Moroccan Middle Atlas, cedar forest is the single most important habitat of the Barbary macaque. As a source of blossom it is worthless; as structure and winter quarters it is not.

Notable: flowers in autumn rather than spring, unusual among conifers; cones stand upright like little barrels and disintegrate on the tree instead of dropping; not capable of flowering until 25-30 years old; cedarwood oil distilled from twigs for perfumery; in the Middle Atlas its forests are the habitat of the Barbary macaque; red-listed in 2013; trialled in Bavaria+Baden-Württemberg as a climate-change alternative species; to 40m/2m diameter.

North Africa: Morocco and Algeria. The Atlas cedar is confined to the high mountains of northwest Africa: the Middle and High Atlas and the Rif in Morocco, and the Tell Atlas and Aurès in Algeria. It grows there between roughly 1000 and 2200 metres, concentrated between 1400 and 1800 metres. Its total range now covers only a few hundred thousand hectares and is still shrinking; the species has been red-listed since 2013. It has been grown in southern Europe since the mid-19th century and is now planted as a park and avenue tree across central and western Europe, with forestry trials under way in Bavaria and Baden-Württemberg.

In the high Atlas the Atlas cedar forms open mountain forest, partly in pure stands and partly mixed with Algerian fir, pines and holm oak. The climate there is Mediterranean-montane: wet, cold winters with snow and hot, rainless summers, with annual rainfall between 800 and 1500 millimetres. It asks little of the soil and grows on limestone as readily as on silicate, provided the ground is deep enough and does not hold water; what matters more is that its roots find fissures where moisture is stored. Overgrazing, timber use and increasing summer drought are driving the stands back, with widespread resin flow and premature needle drop on record.