Cupressus dupreziana var. atlantica (Gaussen) Silba

Cupressaceae

One of two varieties of cypress native to North Africa where it occurs in a very restricted area of the Atlas Mountains of Morocco. The severely fragmented population is Crtically Endangered

Associated Names:

azel, cyprès d’Atlas and Moroccan cypress

Description

Habit

Tree 16–18m tall, monoecious; trunk d.b.h. 2–3m. Bark thick, deeply fissured, exfoliating in longitudinal strips. Branches spreading or ascending, forming a conical or pyramidal tree

Foliage

Spreading or drooping to pendulous. Leaves, scale-like (all equal in size), arranged in opposite pairs at right angles to those above or below, overlapping, gradually tapering, with glands, stomata few and scattered on margins near leaf base; shiny greyish-green or glaucous green.

Cones

Male pollen-cones on branches close to female cones, solitary, terminal, ovoid, 4–6 x 2–3mm, yellowish-brown when mature. Female seed-cones solitary on lateral branches, terminal on short leafy branchlets, ovoid-oblong, 15–27 x 13–21mm, light brown when mature; bract-scale complexes 10–12 in opposite pairs at right angles to those above or below. Seeds 6–8mm, closely packed, ovoid-globose, more or less angular, flattened, dark brown, wings 2 on opposite sides, 1–2mm wide.

Notes

The differences between C. dupreziana var dupreziana and C. dupreziana var. atlantica are that the former taxon has ovoid-oblong seed cones with ca 12 bract-scale complexes and the seeds are not angular.

This variety has previously been described as a separate species – C. atlantica (Gaussen, 1950) but both Farjon (2005) and Silba (1998) consider it to be morphologically very close to C. dupreziana. Likewise, from both the morphological and phytochemical studies (Griffiths,1998) it is thought that Cupressus atlantica is a subspecies of C. dupreziana (and very separate from C. sempervirens). Recent research (Rushforth, et al, 2003; Sekiewicz et al. 2016) suggests that C. atlantica should be considered as a distinct species from C. sempervirens and C. dupreziana. However more molecular work is required to confirm its true taxonomic status.

Distribution

Endemic to Morocco in the Region of Marrakech-Tensift-El Haouz and the Province of Marrakech. The precise area is located in the Oued n'Fiss Valley 60 km south of Marakech, between Tizi-n-Test road, south of Asni. In total there are 8 sites (Bellefontaine, 1979) which together represent a single location. The current actual area of occupancy is estimated to be 14.58km² (Achhal, 1986) while the extent of occurrence, based on recent herbarium specimens from across its known range, is 40km². The taxon consists of a single population within a single location. From a ground survey (using binoculars) of four of the eight known locations estimated that the number of individuals is at least 6,650 trees (Tigouramine – 100; Targa-n-Ait Iratene – 200; Rikt – 1,350; Achachi – 5,000+) (Griffiths, 1998). Estimates of the actual Area of Occupancy indicates a reduction from c.55km² (Boudy, 1950) to only 14.58km² (Achhal, 1986) which over a 36 year period gives a reduction of some 73% (Griffiths, 1998). Most trees are semi-mature to mature and in excess of 100 year old (Boudy, 1950 ; Bellefontaine, 1969; Griffiths, 1998). The most recent survey indicated that the area of woodland with Cupressus was c.1660ha (Sekiewicz 2014)

Habitat and Ecology

Grows in a temperate semi-arid to dry Mediterranean climate with periods of drought and snow. All stands occur on steep-sided mountain slopes in an altitudinal range of between 1,000 and 1,800 m. Three of the four stands are growing on south-east facing slopes, the stand at Targa-n-Ait Iratene is on a north-facing slope. The substrate is shale or schist and crystalline soils of granites and occasionally of calcareous soils which are unstable and constantly eroding (Bellefontaine, 1979; Achhal, 1986; Sekiewicz 2014). Associated woody species include: Juniperus phoenicea and Tetraclinis articulata with the shrubs: Lavandula dentata var. dentata, L. maroccana, Launaea arborescens and Waronia saharae and the herbs include: Carlina brachylepis Cymbopogon schoenanthus, Eryngium ilicfolium, Globularia alypum, Linaria ventricosa, Ononis natrix and Polygala balansae.

Human Uses

Historically, the wood was utilized for making joists and beams in order to build houses and in the building of large gates for the entrances of old town walls (Bellefontaine, 1979; Achhal, 1986). The larger branches of the trees were utilized to make chairs and tables and other furniture and the smaller branches were collected during the summer and stored for winter feed for the local Berber herds of goats and donkeys. Today substantial amounts of seeds are collected annually for commercial horticulture

Conservation Status

Global status and rationale

Critically Endangered B1ab(ii,iii,v)

Cupressus dupreziana var atlantica has undergone a recent decline of 73% over a 36 year period (1950–1986) in the area of occupancy. This decline is sufficient for an assessment of Endangered under A2 criteria. However, the estimated current extent of occurrence is 40km² which is within the 100km² threshold for Critically Endangered under the B1 criteria. It is known from a single location where the primary threat across that range comes from overgrazing and an associated lack of regeneration. Secondary threats include over-collection of seed. In addition, there is a continuing decline in the quality of habitat and the number of mature individuals. According to IUCN guidelines, the highest category of threat should be used and therefore an assessment of Critically Endangered is warranted.

Global threats

Threats include seed collecting, grazing and climate change. During a survey undertaken by Griffiths (1998) it was found that much damage was caused to the trees by local Berbers who were collecting seed unsustainably for commercial horticultural use in Marrakech. The survey found that 84% of the trees were either severely or moderately damaged, 14% had little damage and only 2% of the trees had no damage. Grazing by goats and donkeys in all four stands studied is also a problem and is on a large scale involving large numbers of animals. Such grazing pressures has a detrimental effect on regeneration (Bellefontaine, 1979; Achhal, 1986), this is also substantiated by local Berbers (Griffiths, 1998). Germination tests concluded that the seeds are viable in all four locations but it is not just the pressures of excessive grazing that prevent regeneration but also the steep, constantly eroding slopes.
According to the Direction des Eaux et Forêts State the climate has changed noticeably over recent years and as a result there is less rainfall and higher summer temperatures (Griffiths, 1998).

Conservation Actions

Some conservation strategies have been implemented by the Direction des Eaux et Forêts including fencing off the sub-populations of Rikt and Achachi and at the former some replanting has been carried but due to lack of after care the survival rate has been low (Griffiths, 1998). It is cultivated in botanic gardens and arboreta in Europe and the USA.