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A SHORT NOTE ON THE ECOLOGICAL STATUS OF CEDARWOOD ATLAS: Cedrus atlantica (Endl.) Carr.
Copyright © Tony Burfield Dec
2004. |
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Pre-amble.
A small number of essential oil
users have questioned the advice in Cropwatch 5
and in my lectures to the oil trade, that Cedarwood Atlas should be
regarded as a potentially threatened species, and that the use of aromatic
commodities from this tree should be actively discouraged. These queries
apparently arise from a lack of easily located Internet references on the
subject (in spite of the fact that deforestation in Morocco has proceeded
at an alarming rate in recent times). In practice, many essential oil
users may rely on more limited and potentially biased sales propaganda
from their oil suppliers for ecological information – although it is often
difficult to find a classically trained biologist or ecologist amongst
their number. One such essential oil seller’s website somewhat vaguely
states: “Cedrus atlantica from North Africa which does need
careful watching but the Morroccan (sic) government is not stupid and the
trees are under specific Royal patronage.” In my opinion, these latter
remarks gloss over the real facts, since, as is explained below, the Atlas
Mountains where Cedrus atlantica is naturally found, is the
principal contender for the Mediterranean Red Alert areas (see
http://www.eco-action.org/dod/no10/empire-task2.htm),
10,000 km2 of Moroccan forest having disappeared between 1940
and 1982 (WWF, undated). UNICED (1994) & Thirgood (1984) reported that in
the last three decades 40% of Morocco’s forests had succumbed to
desertification or degradation. So, it is even more inexplicable that
certifying agencies such as Ecocert and the Soil Association have felt
themselves able to endorse aromatic commodities such as Cedarwood Oil
Atlas which originate from these critically endangered areas (see below)
as qualifying for “organic” status.
The
identification of Sites of Biological and Ecological Interest by the Water
and Forest Directorate of the Forests and Water Ministry of Morocco, and
the launching of a World Bank/Global Environment Facility project on
biodiversity conservation by the Moroccan Government, are reported by WWF
(undated). They further report “the enlargement of the national protected
areas network, creation of new national parks, declare a number of these
priority sites as nature reserves, and improve the management systems of
13 areas, by establishing management plans, improving local capacity, and
involving local populations in nature resource management are amongst the
goals”.
1. Cedrus species: background. The
Cedrus genus itself is generally divided into four separate species, but
other classifications have reduced the number to two. For example Cedarwood
Atlas: Cedrus atlantica (Endl.) Carr is classified by some workers as
a geographical subspecies of Cedar of Lebanon, and so becomes Cedrus
libani subsp. atlantica (Endl.) Batt. & Trabut. We can briefly
summarise these classifications in a table as follows:
Table 1:
True Cedarwoods: common & botanical names and ecological status.
A detailed review of the Cedarwood oils has
been published (Burfield 2002, 2003a, 2003b).
2. Ecological status of forests containing
Cedrus atlantica.
The disappearing Mediterranean conifer forests
& eco-regions of N. Africa specifically extend over N. Morocco, N. Tunisia
and N.W. Algeria. A non-peer reviewed, but informative paper by the World
Wildlife Fund (WWF undated) describes
the conservation status of these
conifer forests as Critical / Endangered.
The conifer zone of
Morocco is described in the same article as consisting largely of Cedrus
atlantica together with other species, according to location – indeed
the Atlas Cedar in strongly associated with Morocco’s ancient forests in
literature covering the last 5,000 years (Mardaga 1999).
Many of the taxa found in the Moroccan conifer forests
are amongst some two hundred included as threatened species in the IUCN Red
List (2004) for Morocco; some additional species (WWF undated) are tabulated
below.
Tazi M. et al. present a modest program for the
conservation of plant genetic resources of Morocco in the face of the
present genetic erosion at
http://apps3.fao.org/wiews/Morocco/Paper6.htm.
Conifer
Forests (after WWF: undated)
The status of cedarwood forests is further
explained in a 1997 document on Morocco’s Protected Areas Management Project
which can be seen at
http://www.gefweb.org/wprogram/mor-anxa.doc,
which describes the Ifrane National park in the Moyen-Atlas central (54,000
ha) essentially based on Cedrus atlantica. (Benabid 2000 reports
C. atlantica with Quercus faginea, Quercus rotundifolia, Pinus
pinaster var. maghrebiana & Juniperus thruifera amongst
the 600-700 endemic spp.)
Mixed forest area in
High Atlas The
Bou Iblane I area (12,000 hectares) is similarly described (part of site is
Cedrus atlantica mixed with green oak Quercus rotundifolia and
part with the juniper tree species Juniperus thurifera),
which is legally unprotected:
young cedar trees are uprooted to
provide winter grazing for livestock and
juniper forerst is degrading from overgrazing. The Jbel Tichoukt area
(12,000 ha), also with cedar forest
threatened by overgrazing by livestock, is
further described. In many areas, in addition to overgrazing threats, the uncontrolled gathering of firewood/illegal logging by local peoples whose needs are not being met, is threatening the survival of Cedarwood Atlas trees; other threats include fire. WWF (undated) refers to the transformation in Berber life from a semi-Nomadic existence to a more settled permanence as putting an un-met requirement for fuel, as being a factor in illegal logging.
A Berber Village in the High Atlas A
thesis on hearth fuel acquisition in the Imnane valley in Morocco’s High
Atlas at http://peacecorps.mtu.edu/DownsCM.pdf may provide some insight on
such communities that depend on wood fuels, to the reader. However these
problems are longstanding: a 1988 article on Toubkal National Park at
http://ims.wcmc.org.uk/IPIECA2/sitesht/1120v.html
refer to these very same factors (uncontrolled herding, illegal timber &
wood extraction, fire) with little/no active conservation management being
evident. Ciani A.C. & Castillo P. (undated)
describe a dramatic increase in forest
degradation due to overgrazing since the
1970’s (including the cutting of vegetation from cedar trees by axe which
eventually kills the tree which causes very severe damage). The authors also
describe the effects of the 1991-1996 drought in the Middle Atlas, where the
water table dropped severely, and debarking of cedar trees by Barbary
macaques further degraded the cedar forest.
Specific information
on illegal logging is difficult to obtain; Hmamouchi (2001a) refers to
the illegal felling of trees and
illegal clearing as
amongst the principal obstacles to the
development of plant medicine in Morocco.
Ciani A.C. & Castillo P. (undated) report that the legal logging of cedar
trees by Eaux et Forets Dept. of the Ministry of Agriculture proceeds
according to management plans, but the rate of extraction is based on the
over-optimistic capability of existing forest regeneration policies.
Benabid
(2000) also documents the following areas as containing Cedrus atlantica
trees: Bou Naucer (high mountain region in the Moyen Atlas Oriental covering
14,000 ha); Parc Nationale de Talassemtane (Rif Central Occidental covering
60,000 ha); Parc Nationale de Tazekka (northern part of Moyen Atlas Oriental
12,000 ha); Parc Nationale du Haute Atlas Oriental (49,000 ha). Whilst
Cedarwood Atlas trees appears to be well conserved in specific areas of
parkland, the ecosystem is very fragile - often the margins are subject to
degradation by erosion, demineralisation, dehydration, desertification etc.
resulting in areas of complete desolation [Pujos (1986); Benabid (1982) &
(1985); M’hirit (1982); Quezel et al. (1987) – all through Benabid
(2000)]. Benabid (2000) for example describes the areas of the Moyen Atlas
Plissé and High Atlas Oriental regions as ecologically fragile, subject to
desertification, and unfavourable for Cedars, those present often being
found dead or damaged.
3. Cedarwood Commodities: Cedarwood Oil Atlas
is produced by steam distillation or high pressure steam distillation of the
wood at a yield of 3-5% from the branches, waste wood, and especially the
sawdust of the pyramidal Cedrus atlantica tree itself, which has not
been described in detail here so far. It is an ascendingly branched tree,
with evergreen needles, which can grow up to 50m. or exceptionally to 65m.
at an elevation of 1400-2500m. in humid and cold subhumid zones. It survives
on several different types of soil in the 133,653 hectares of Cedar forest
(according to Mardaga 1999) in the Middle Atlas, Rif central and Grand Atlas
Oriental, and the Middle Atlas Oriental areas of Morocco, where Cedar forest
might constitute some 2.8% of the total area of Moroccan forest (Mardarga
1999). The tree also grows in N.W. Algeria, scattered widely over 300 km2
in the Tellien Atlas. Cultivars of the tree have been imported into N.
America (especially into milder parts of British Columbia) & Canada as
ornamentals - the cultivar C. atlantica f. glauca (Blue Cedar)
is especially admired for its blue foliage. It is used as a reforestation
tree in France, Italy, Bulgaria etc., but it is susceptible to pest attacks
when grown in Europe [Ciani & Castillo (undated)]. Essential
oil production in Morocco was estimated at 7 tons per annum by Lawrence
(1985) but levels of Cedarwood Atlas concrete production tonnage
(solvent extraction of the wood by cyclohexane or other solvents – benzene
was formerly used) are unrecorded. Cedarwood Atlas concrete (anomalously
called a “resinoid”) does find some use in perfumery because of its
good fixative properties and finer odour than the oil (Arctander 1960). The
more valued “absolute” is produced from the concrete by fractional
distillation. The essential oil nowadays has limited uses in perfumery
because of its strong detracting urinic odour compared with the finer notes
of the oil of Cedarwood Virginian. However, a 1936 edition of Poucher (Poucher
1936) desribes a mimosa aspect to the oil, and indicates that the double
rectified oil of Cedrus atlantica was, at the time, considered of use
in soap perfumery, the terpeneless oil useful in perfumery and the solvent
extracted resinoid useful in soap fragrancing in spite of its dark colour. A
Moroccan medical plant reference book (Hmamouchi M. 2001) only describes the
traditional use (wood, leaves) as an anti-inflammatory for rheumatism, but
warns of neurotoxic effects. Gattefossé reports on Massey’s therapeutic
study of Cedarwood Atlas and its uses in venerology a centaury ago (Gattefossé
1937); the oil has since been successfully marketed into aromatherapy, where
it is employed for its’ antiseptic, anticatarrhal, circulatory stimulant and
expectorant properties.
The Cedarwood Atlas tree has been important in the
socio-economy of Morocco, being suitable for furniture making, carpentry,
construction work, and by dry-distillation, for tar-making. Benabid (2000)
also mentions that the leaves (needles) are using in tanning. Like all
cedarwoods, the wood it is fragrant, insect repellent and rot-resistant due
to the essential oil content. However it is not known with any certainty,
what level of extra pressure on the shrinking conifer forests, or the wider
environmental impact implications that the continued extraction of essential
oil & resin from the tree has had. Further, the skin sensitivity problems
associated with the production of fragrant lichen products from oakmoss (Evernia
prunastri) & treemoss (Pseudoevernia
furfuracea
mixed with
Usnea
spp.)
qualities which are used in perfumery, have led to an much-increased demand
for Moroccan Cedarmoss extracts (from the lichen Evernia
furfuracea), which grow on, and are gathered from, Cedarwood Atlas
trees.
Heavy
growth of Cedarmoss on a
The author has not been able to find any
damage/impact data relating to the increased rate of gathering of Cedarmoss
from Cedarwood forests; however Ciani A.C. & Castillo P. (undated) describe
the economic production of this activity- and other cedar forest activities
such as essential oil production, honey-bee breeding and ethno-medicinal
production - as being low.
Margot (1999) in a major work on the Moroccan forest
system describes the explains the necessity for silviculture in Morocco’s
natural forest and describes schemes of regeneration for Cedarwood Atlas in
plantations stretching over 120 years and involving thinning developing
trees down from a rate of 5,000 per hectare down to an eventual 100 per
hectare - by which time the trunk diameter is 30cm (at 120 years plus). As
we have seen in previous Cropwatch reports with similar long-maturing tree
schemes (Sandalwood East Indian, Rosewood Brazilian) (see
http://www.users.globalnet.co.uk/~nodice/)
these plans for sustainability may be commendable in some respects, but may
have too much built-in vulnerability to be relied on totally. Conclusion. It is apparent that stricter management of the critically endangered and rapidly diminishing conifer forest areas of Morocco, in conjunction with meeting the basic needs of local people, is still an urgent priority. Meanwhile the exploitation of shrinking conifer forests for Cedarmoss, Cedarwood oil Atlas, its resinoid and absolute, by the aroma trade should be halted right now, in my opinion, until a comprehensive environmental impact study is available, the area is adequately conserved, and adequate resources for natural regeneration are available.
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Glossary. An
acre = 4,046 square metres (m2)
= 0.405 hectare A
hectare = 10,000 square metres (m2)
= 2.471 acres = 0.01 square
A square kilometre =
1,000,000 square metre = 100 hectares = 247.105381 Acres = 0.386102 square
miles. References. Arctander S. (1960)
Perfume & Flavour Materials of Natural Origin Elizabeth NJ (USA).
Benabid A. (1982)
Etudes phytoécologique, biogéographique, et dynamique des associations et
séries sylvatiques du Rif occidental (Maroc). Thèse Docr. ès- Sc. Fac.
Sci. et Tech. St-Jérôme, Aix-Marseille III, 199p. + Annexes. Benabid A. (1985) Les
Ecosystèmes forestiers Maricaines: Diversité, biogégraphie et degradation.
Forêt méditerranéenne, Marseillle, T.7. Benabid A. (2000)
Flore et Écosystèmes du Maroc Éditions Ibis Press, Paris, 2000. Burfield (2002)
“Cedarwood Oils – Part One” Aromatherapy Times Vol 1(55)
Winter 2002 pp 14-15. Burfield (2003a) “Cedarwood
Oil - Part 2” Aromatherapy Times Spring 2003 Vol 1(56)
p14-16.
Burfield (2003b) “Cedarwood
Oil – Part 3: Therapeutic Properties” Aromatherapy
Times, Summer 2003 Vol 1(57) pp 16-18.
Ciani A.C. & Castillo
P. (undated) “The Desertification Process in the last natural forest of the
Southern Meditteranean Region” – see
http://www.psy.unipd.it/~eto/testi/articoli/cretepau.html Gattefossé R.-M. (1937)
Aromathérapie les Huilles Essentielles Hormones Végétales Gardot et
Cie Paris 1937. Hmamouchi M. (2001) Les
Plantes Medicinales et Atomatiques Marocaines (pvt publicn) 2nd
edn 2001 p67.
Hmamouchi M. (2001)
ibid p25. IUCN (2004):
Conifer Specialist Group 1998. Cedrus libani var. libani. In:
IUCN 2004. 2004 IUCN Red List of Threatened Species. <www.redlist.org>.
Khuri S.
“Conservation of the Cedrus libani
populations in Lebanon: history, current status and experimental application
of somatic embryogenesis” Biodiversity and Conservation 9
(9): 1261-1273, September 2000.
Lawrence B.M. (1985): “A review of the
world production of essential oils (1984)” Perf. Flav. 10(5)
1-16. Maheshwari P & Biswas C.
(1970) “Botanical Monograph No. 5 - Cedrus” CSIRA New Delhi p3.
Mardaga (1999) Le grand livre de la Foret Morocaine pub.
P. Amardaga Spimont (Belgium) 1999. M’hirit O.
(1982) Etude écologique et forestière des cédraies du Rif Marocain.
Ann. Rech. Forest. No. 22. S.R.F. Rabat.
Poucher W.A. (1936)
Perfumes, Cosmetics and Soaps Vol 1 Chapman & Hall, London 4th
edn 1936 p 49-50. Pujos A. (1966) “Les milieux
de la cedraine Marocaine” Ann. Rech. Forest., Rabat, 8, 283.
Quezel P., Barbero M. &
Benabid A. (1987) “Contribution à l’étude des groupements forestiers et
préforestiers du Haut Atlas oriental (Maroc)” Ecol. Medit. Marseille,
13(1/2), 107-117.
Tazi M. , Birouk A. , Mellas H. & Maghnouj M. “Plant
genetic resources conservation and documentation in Morocco” – see
http://apps3.fao.org/wiews/Morocco/Paper6.htm Thirgood, J.V. (1984)
The Demise of Barbary Macaque Habitat - Past and Present Forest Cover of the
Maghreb. pp 19 - 69 in The Barbary Macaque. A case study in conservation.
J.E. Fa, ed. New York, Plenum Press, 1984. NCED (1994) United Nation
convention to combat desertification in those countries experiencing serious
drought and/or desertification, particularly in Africa. New York, 1994
[through Ciani A.C. & Castillo P. (undated) above].
Vidakovic, Mirko (1991)
Conifers: morphology and variation. Translated from Croatian by Maja
Soljan. Croatia: Graficki Zavod Hrvatske. WWF
(undated) – see:
http://www.worldwildlife.org/wildworld/profiles/terrestrial/pa/pa0513_full.html
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