Technical guidelines are targeted to practical forest managers and provide summarized information on the biology and ecology of tree species, distribution ranges, importance and use, genetic knowledge, threats to genetic diversity and recommendations for long-term genetic conservation. For the full list of Technical guidelines produced, please visit http://www.euforgen.org/publications/technical_guidelines.htm

Bozic, G.

Gugerli, F.

Ulber, M.

CGSpace

Pinus cembra L. is a five-needledpine tree (subgenus Strobus,section Cembra, subsectionCembrae). The species rarelyexceeds heights of 25 m, itsgrowth is very slow but long-lasting and trees between 500and 1000 years of ageare reported. Undernatural conditions,it may take 30years to reach1.30 m. Owing toits slow growth, P.cembra is a weakcompetitor com-pared with othertrees. However, it isbetter adapted to theharsh upper subalpineclimate conditions thanany other European treespecies. Consequently, itcan compete in mixed standswhere the performance of theother subalpine trees (mainlyPicea abies and Larix decidua) isreduced and establish purestands above their growth limit.Pinus cembra is often associatedwith Pinus mugo, L. deciduaand/or P. abies.Stone pine tends to be a cli-max species tolerating someshade in the juvenile stage andgerminating well on organic soilswith an accumulated layer of lit-ter and moss. However, it cangerminate and establish itself onmineral soils or even rocky sur-faces as well.The slow juvenile growth of P.cembra makes the species vul-nerable to browsing for a longtime and susceptible to lethalfungus infestations occurringunder prolonged snow cover. Forthe latter reason, P. cembra isnot found in microhabitats orregions with long-lasting snowcover (e.g. border zones of theAlps).Stone pine is a wind-pollinated species with male andfemale flowers on the same tree(monoecious). Within naturalstands, reproductive maturity isnot reached before plants are40–60 years of age. Floweringand seed production occur every2–3 years, but only a single yearPinus cembraThese Technical Guidelines are intended to assist those who cherish the valuable Swiss stonepine genepool and its inheritance, through conserving valuable seed sources or use in practicalforestry. The focus is on conserving the genetic diversity of the species at the European scale.The recommendations provided in this module should be regarded as a commonly agreed basisto be complemented and further developed in local, national or regional conditions. TheGuidelines are based on the available knowledge of the species and on widely acceptedmethods for the conservation of forest genetic resources.Swiss stone pineMarcus Ulber1, Felix Gugerli1 and Gregor Bozic21Section Ecological Genetics, Swiss Federal Research InstituteWSL, Birmensdorf, Switzerland2Slovenian Forestry Institute, Ljubljana, SloveniaTechnical guidelines for genetic conservation and useBiology and ecologyEUFORGENout of 4–10 is an abundant mastyear. Self-fertilization is possible.The seeds ripen in the year afterpollination, but the conesremain closed and do notrelease the heavy, winglessseeds. The seeds are most-ly dispersed by the Europeannutcracker (Nucifraga caryocat-actes), a bird species with astrong mutualistic relationshipwith P. cembra. The nutcrackerpicks most of the cones from thetrees and caches those seeds itdoes not immediately eat inshallow underground depositsas a food source for the winter.A single nutcracker may storemore than 25 000 seeds everyyear. Dispersal distances can beas far as 15 km horizontally and700 m altitudinally. Most of thedeposits are retrieved and emp-tied by the bird during winter andspring, but some are left, manyof them in sites suitable forgermination and sur-vival of P. cembra,resulting in a sufficientand regular regenerationof the tree. Tree clusters(with either separated orfused trunks) originating frommore than one germinated seedfrom one deposit arefrequent andimprove the stabil-ity of the sub-alpine forest. The distribution range ofthe Swiss stone pine issmall compared with oth-er pine species. It isrestricted to the sub-alpine belt in the con-tinental (i.e. central)parts of the Alps(France, Italy, Switzerland,Austria, Germany) and to somehigher regions of the CarpathianMountains (isolated patchesfrom Tatra Mountains in Slovakiaand Poland to the SouthernCarpathians in Ukraine andRomania). The total species'coverage was estimated asabout 30 000 hectares (density-weighted area) in the 1970s.The altitudinal range of P.cembra forests is from 1500 to2400 m asl (single individuals1200–2850 m) in the Alps andfrom 1300 to 1700 m asl(900–1985 m) in the Carpathi-ans. The lower boundary isdetermined by the competition ofother tree species (mainly P.abies), whereas the upper limitseems to be a physiological (cli-matic) boundary.The likely origin of P. cembraseems to be in the Siberianregion, where its closest relative,P. sibirica (treated as P. cembravar. sibirica or P. cembra subsp.sibirica by some authors), coversvast areas. It is supposed tohave survived the last glaciationperiod in the vicinity of the Alpineand Carpathian mountainranges from where itcould expand in anearly postglacialphase to occupylarge areas. Atlower alti-tudes it wassubsequent-ly replaced.DistributionPinus cembra PinSwiss stone pinePinus cembraSwiss stone pinePinus cembraSwiss stone pinePinus cemWherever it occurs naturally, P.cembra contributes to the upper-most forest belt in themountains, forming mixedor pure stands. Conse-quently, the specieshas a crucialprotectivefunction forthe surround-ing area. Thepresence of(evergreen)trees in thestone pine's altitudinalzone helps to minimize the risk ofavalanches and soil erosion.Pinus cembra is, therefore, val-ued as a stabilizing factor andoften used for afforestation athigh elevations.Stone pine forests (pure andmixed) have a high aesthetic andornamental value for manyregions famous for summer andwinter tourism.Besides the protective andaesthetic functions of thespecies, the timber of P. cembrais highly valued, especially forpaneling, carvings and traditionalfurniture because of its specialwood characteristics (soft, light,resistant, warm reddish colour,perfume of resin). However, thetraded quantities are compara-tively small and mainly serve thelocal markets.In concordance with the putativesurvival areas during the lastglaciation, isozymevariation indicatesa low degree ofgenetic differen-tiation between astone pine populationfrom the Carpathianmountains and the popula-tions from the Alps. Most ofthe genetic diversity found inCarpathian stands resideswithin populations. This alsoholds for the Alpine range, wherethe two main distribution areas inthe eastern and the western Alpscannot be separated based onchloroplast diversity owing toextended historical pollen flow.However, there is a reducedgenetic variation in isolated pop-ulations at the northern margin ofthe Swiss Alps. Crown forms for-merly recognized as distinctraces are consideredto be the result ofenvironmental effectsrather than deservingof taxonomic status.However, elevationalvariation was observedwith respect to growthresponse in common gar-den experiments. Further-more, it remains openwhether the occurrence ofgreen instead of violet coneshas a genetic background.Owing to its ecological charac-teristics (weak competitiveness)and to negative anthropogenicimpact (overuse, deforestation,intentional burning for gaininggrassland), the occurrence of P.cembra today is highly fragment-ed in parts of its distributionrange, and small populationsizes are common.The fragmentation may inhibitgene flow among the populations.Small populations are generallyprone to elevated inbreeding andgenetic erosion, but they arespecifically threatened in anunstable area such as subalpineregions by avalanches, forestfires, landslides or unusual cli-matic events which can lead tofurther dramatic losses of geneticinformation.Threats togenetic diversityImportance and use Genetic knowledgenus cembra PinusembraSwiss stone pinePinus cembraSwiss stone pinePinus cembraSwiss stone pinePinA specific problem of many P.cembra stands is the highlyskewed age distribution owing toa lack of recruitment and youngtrees (often as a result of brows-ing or other damages by ungu-lates or grazing livestock). Ifthose stands cannot be regener-ated, these populations risk losing some of their geneticinformation in the short term andextinction in the long term. Fur-thermore, high ozone loadsseem to cause a decline of P.cembra, whereas the specieshas shown a higher degree ofresistance to other air pollutantsthan do sympatric pine species.An altitudinal cline of growthcharacteristics has beenobserved in provenancetests showing that P.cembra performs best inthe altitudinal zone fromwhich it originates. Oncethe growth belt of stonepine is reduced to a nar-row altitudinal strip and thegenepool is depleted, thecapability of the species tospread out again is thereforelimited.The main strategy of geneticconservation of Swiss stone pineshould be a dynamic in situ con-servation. However, complemen-tary dynamic or static ex situconservation may be appropriatein some cases.In situ conservation can bedone within natural forestreserves, in gene conservationunits specifically managed forthe purpose, as well as in forestsmanaged mainly for other pur-poses. Generally, abundant andlarge stands of interfertileautochthonous stone pinetrees are best to assuregenetic adaptability andadaptedness in the longterm. However, small andisolated populations of P.cembra can be of specialinterest if particular adapta-tions can be assumed.Normally, gene conser-vation can be matchedwith other goals of thestand management. Asmany of the P. cem-bra forests areexpected to fulfilprotection and/oraesthetic functions, a continuoustree cover is needed. A suffi-ciently dense, multilayered,uneven-aged forest with a clus-tered structure meets thesedemands best. Small-scale silvi-cultural practices such as thegroup selection method or thecluster selection method are rec-ommended for both wood pro-duction and protection purpos-es. Where stone pine is naturallymixed with other tree species it isadvisable to retain the mixture.The crucial point in any casefor a dynamic in situ gene con-servation is the regeneration ofthe stand. Natural regeneration isconsidered to be the best wayfor gene conservation.If there are suitable germina-tion sites and seed trees withinthe nutcracker's dispersal range,regeneration of P. cembraoccurs naturally. Sometimes avery dense cover of grasses orAlpine roses can be an obstaclefor seedling growth, and theremoval of patches of this vege-tation can be useful. If necessary,animals affecting the youngplants have to be excluded orindividual protection measuresmust be taken. Forest gapssmaller in diameter than theheight of the surrounding standtend to accumulate snow duringthe winter and become snow-free only late in spring. Therefore,the dimensions of regenerationgaps should be 1–4 times thestand height depending on thesite conditions.For artificial regeneration inexisting stands or for high-elevation afforestations with P.cembra, reproductive materialmust be chosen carefully owingto extreme site conditions. Onlywell-adapted and sufficientlyvariable material originating fromsimilar sites ensures a long-termsuccess for both production andGuidelines for geneticconservation and uses cembra Pinus cPinus cembraSwiss stone pinePinus cembraSwiss stone pinePinus cembraSwiss stone pprotection purposes. For plant-ations near the tree limit, theprovenance of the materialshould lie within a 100-metre alti-tude range relative to the plant-ing site. It is suggested to breedthe plants in montane altitudesand to transplant them into anursery located above 1500 masl to ensure hardy acclimatiz-ation. Direct seeding has provento be a satisfactory alternative toplanting. As a consequence ofthe erratic seed production andthe slow growth process, theplanning of a plantation shouldstart well in advance. Seedorchards at lower altitudes con-taining high-elevation pro-venances can facilitate a moreregular supply of seeds.Seed orchards can serve as ameans of dynamic ex situ con-servation of P. cembra if thenumber of progenies is suffi-ciently high (at least 50 trees pro-posed per origin population),especially in the case of en-dangered small or relic popula-tions. However, it is preferable toconduct dynamic ex situ conserv-ation in the vicinity of the originalsite and to use the local material.This is what the nutcracker tendsto do when it "salvages" thespecies from accessible spots torocky outcrops where theseedlings may survive.Static ex situ conservation ofreproductive material of P. cem-bra for gene conservation pur-poses is advisable only in case ofemergency and the materialshould be recultivated as soonas possible.Pinus cembra PSwiss stone pinePinus cembraSwiss stone pinePinus cembraSwiss stone pinePDistribution range of Swiss stonepinewww.euforgen.orgMore informationPinus cembra PinThese Technical Guidelines wereproduced by members of theEUFORGEN Conifers Network.The objective of the Network is toidentify minimum genetic conser-vation requirements in the longterm in Europe, in order to reducethe overall conservation cost andto improve the quality of stan-dards in each country.Citation: Ulber, M., F. Gugerli andG. Bozic. 2004. EUFORGENTechnical Guidelines for geneticconservation and use for Swissstone pine (Pinus cembra). Inter-national Plant Genetic ResourcesInstitute, Rome, Italy. 6 pages.Drawings: Pinus cembra, ClaudioGiordano. © IPGRI, 2003.ISBN 92-9043-619-0EUFORGEN Secretariat c/o IPGRIVia dei Tre Denari, 472/a00057 Maccarese (Fiumicino)Rome, ItalyTel. (+39)066118251Fax: (+39)0661979661euf_secretariat@cgiar.orgePinus cembraSwiss stone pinePinus cembraSwiss stone pinePinus cembraSwiss stonSelected bibliographyContini, L. and Y. Lavarello. 1982. Le Pin Cembro (Pinus cembra L.) – Réparti-tion, écologie, sylviculture et production. INRA. 197 p.Gugerli, F., M. Anzidei, A. Madaghiele, U. Büchler, C. Sperisen, J. Senn andG.G. Vendramin. 2001. Chloroplast microsatellites and mitochondrial nad1intron 2 sequences indicate phylogeographic relationship of Swiss stonepine (Pinus cembra), Siberian stone pine (P. sibirica), and Siberian dwarfpine (P. pumila). Molecular Ecology 10:1489–1497Holzer, K. 1975. Genetics of Pinus cembra L. Annales Forestales 6/5:139-158.Rikli, M. 1909. Die Arve in der Schweiz – Ein Beitrag zur Waldgeschichte undWaldwirtschaft der Schweizer Alpen. N. Denkschr. Schweiz. nat. forsch.Ges. XLIV. 455 p.Schmidt, W.C. and F.-K. Holtmeier, compilers. 1994. Proceedings of the Inter-national Workshop on Subalpine Stone Pines and Their Environment: theStatus of Our Knowledge. St. Moritz, Switzerland, 5–11 September 1992.Gen. Tech. Rep. INT-GTR-309. U.S. Department of Agriculture, Forest Ser-vice, Intermountain Research Station, Ogden, UT. 321 p.Schütt, P. 2000. Pinus cembra Linné, 1753. In Schütt P., H. Weisgerber, H.J.Schuck, U. Lang and A. Roloff, eds. Enzyklopädie der Holzgewächse. 16thvolume, ecomed-Verlag, Landsberg/Lech, 18 p.EUFORGEN

Swiss stone pine (Pinus cembra)

https://cgspace.cgiar.org/bitstream/10568/104342/3/Swiss_stone_pine_Pinus_cembra_928.pdf

Swiss stone pine (Pinus cembra)

Abstract

Similar works

Full text

Available Versions

CGSpace