How to balance forestry and biodiversity conservation – A view across Europe

298 Hèches – ‘Groupement Forestier des montagnes particulières de’: a case from the mountains of southwestern France C 9 L. Larrieu1, G. Verdier 2 1 INRAE, UMR Dynafor, Castanet-Tolosan, France; CRPF Occitanie, Tarbes, France 2 GF president, Hèches, France

Context, legal frame, and ownership (fig. C 9.1). The forests here have always been mul- structure tifunctional, and have mixed wood production, pastoralism, hunting, and harvesting of mushrooms The private forest area called ‘Groupement Fores- and forest berries. tier (GF) des montagnes particulières de Hèches’ In accordance with the presence of a wide array is located on the northern slope of the central of geological substrates, stands thrive in areas Pyrenees mountains in the region of Occitanie where the soil is thick and nutrient-rich, while in

France

N km 0 0,5 1 2 3 Sources: Esri, Airbus DS, USGS, NGA, NASA, CGIAR, N Robinson, NCEAS, NLS, OS, NMA, Geodatastyrelsen, Rijkswaterstaat, GSA, Geoland, FEMA, Geoland, GSA, Rijkswaterstaat, NMA, Geodatastyrelsen, OS, NLS, NCEAS, Robinson, N CGIAR, NASA, NGA, USGS, DS, Airbus Esri, Sources: Community User GIS the and contributors, OpenStreetMap © USGS, NOAA, FAO, Garmin, HERE, Esri, Sources: community; user GIS the and Intermap

< Fig. C 9.1. Overview of the GF property; beech-fir stands dominate; however, the complex topography and geology favours a wide range of forest habitats. Because of the a very old tradition of livestock farming, grass- lands have replaced the subalpine forest (Photo: Laurent Larrieu).

299 Timber/Biomass

Statement Groundwater Non-timber products “In the context of rapid biodiversity loss and climate change, we must adopt a fully Climate Erosion integrated management approach to try passing on to our children a property which will last centuries while providing Landscape Protection all the ecosystem services we have enjoyed to date.” Recreation Biodiversity

Table C 9.1. General information on the forests of the GF des montagnes particulières de Hèches.

Forest community Mostly mixed beech-fir montane forest (Fagion sylvaticae and Luzulo-Fagion). Locally Tilio-Acerion ravine forests and Cephalante- ro-Fagion dry beech forest Total forest area 930 ha (+272 ha of subalpine meadows) Main management type Selective cutting system Total mean volume Very wide range according to a wide array of soil conditions; from a few m3/ha (rocky soils) to more than 600 m3/ha (thick fertile soils) Annual growth Very variable. More than 10 m3/ha for the most productive stands Deadwood Wide range depending on local conditions and management intensity: from 9 to 60 m3/ha (diameter >10 cm) Altitude 620–1900 m a.s.l. (forest: 620–1500 m) Ownership Private forest; ‘Groupement Forestier’ status Geology 23 different substrates. Four main categories: (i) hard nutrient-rich Mesozoic limestones and dolomites; (ii) soft nutrient-rich Mesozoic clayey limestones and marls; (iii) acidic nutrient-poor Palaeozoic shales, Mesozoic puddingstones (conglomerate), ophite, etc.; and (iv) very acidic and strongly nutrient-poor Palaeozoic quartzite and shales Protected area 0 ha Nature protection area (Natura 2000) 0 ha Protected area for the water spring of the 20 ha with specific constraints on management community Area without harvesting Roughly 200 ha (20 %)

other areas (e.g. on rocky soils and in open sunny carried out by the owners themselves. When areas) the stands are made up of small trees. How- needed, owners can be helped in technical decision ever, the Atlantic macroclimate means that the issues by an adviser from the Centre Regional de la average precipitation is high and the temperatures Propriété Forestière d’Occitanie (CRPFOcc, Occita- are relatively warm (fig. C 9.2), meaning that for- nie Regional Forest Ownership Centre). Except fire- ests can thrive. wood, the wood is sold to independent forest oper- The forest owner group is made up of roughly ators. Every summer, sheep, cows, and horses are 100 local people. The management decision-mak- grazed on the subalpine meadows. The ing body is a board with 14 members led by a pres- belong to two of the owners of the GF, but also to ident. The forest operations and management are livestock farmers who lease the right to graze their

300 C 9 Hèches, France animals on the land. Hunting rights and rights to A group of local farmers bought the property mushroom harvesting are reserved for the GF own- in 1860, with the main aim to use the subalpine ers and village inhabitants. meadows for livestock grazing in summer. Livestock Two of GF’s owners are employed part-time as also used some stands for grazing, particularly the rangers, with one focussing on forest issues and stands alongside paths, and stands located on one focussing on livestock issues. south-facing slopes which are sunny and become free from snow early in spring. Wood products were mostly for domestic use (firewood from Portrait broadleaves, timber from silver fir) or charcoal pro- duction for the local steel industry (that were in “As the president representing the owner set of production until 1943). For charcoal production, the GF, my mission is to apply sustainable and mul- stands were managed according to the coppice tifunctional management that benefits the owners, selection method. This forest history explains the but also the other villagers. The challenge is to rec- current dominance of beech (Fagus sylvatica) at the oncile production of high-quality timber, hosting of expense of silver fir (Abies alba) since grazing, fire livestock, the presence of a large game population and intensive logging favours tree species which allowing traditional hunting activities, and finally can sprout. harvesting of edible mushrooms and berries. In In the period from the end of World War II to addition, this property is also an area for recrea- 1978, there was very little harvesting. In 1979, the tional activities for people from outside the vil- owners shifted to timber production. However, lage.” summer grazing by livestock remained a necessity. A huge effort to build a road network (about 45 km) combining both truck and dirt roads pro- Forest history and cultural heritage vided access to about 80 % of the area. As beech timber has a high value, the stands were regularly The subalpine meadows have been grazed by live- logged until 2000, and annual harvesting was on stock for >5000 years. Old maps (Cassini’s maps, average about 3000 m3. A drop in wood price 1770; Vallauri et al. 2012) show a forest cover simi- slowed down the rate of logging after 2000 and to lar to the current one. Most of the stands were har- 2010. Since 2010, about 6000 m3 of timber have vested periodically between the seventeenth and been harvested annually. twentieth centuries, mainly for charcoal produc- Stands are mainly composed by naturally regen- tion. In the nineteenth century, the forest owners erated native species (fig. C 9.3). There are only a were also the owners of steel mills. few plantations of non-native conifers (about 10 ha),

a b 180 mm 60°C 25°C

150 mm 50°C 20°C 07 08 120 mm 40°C 06 15°C 09 90 mm 30°C 05 10°C Growing season 60 mm 20°C 10 Precipitatio n Temperature 04 11 5°C 30 mm 10°C 03 12 02 01 0 mm 0°C 0°C 01 02 03 04 05 06 07 08 09 10 11 12 20 mm 40 mm 60 mm 80 mm 100 mm 120 mm 140 mm 160 mm Months Precipitation Fig. C 9.2. Weather data (Hèches, 940 m a.s.l., Aurelhy model, 1981–2010); panel a: ombrothermic diagram using the scale ratio P = 3T since macroclimate is Atlantic; panel b: Climate graph, numbers indicate months.

301 How to balance forestry and biodiversity conservation – A view across Europe including Douglas fir (Pseudotsuga menziesii), black Most important services and products pine (Pinus nigra), European larch (Larix decidua). Some native broadleaved species have also been The wood sale is the most important income for the planted, including sycamore (Acer pseudoplatanus), owners, mostly timber (about 30–45 % of the vol- wild cherry (Prunus avium), and beech (about 20 ha). ume) (fig. C 9.4). The main expense is due to the The conifers were planted in 1992 and the maintenance of the road network (fig. C 9.5). broadleaves were planted in 1997, on ancient graz- ing or burned areas. The water spring, used for decades by the Conservation interest – habitats and rare whole village, is located on the property. A new species protection buffer has been set up in 2000, strictly protecting about 0.2 ha and constraining the Eighteen habitat types have been identified, includ- management of forest on the 20 ha around the ing forest and non-forest habitats (Pénin and Lar- spring. gier 2000). Biological inventories revealed the pres- ence of 374 species of (including some rare species such as Teredus cylindricus, Denticollis Aims of the owners rubens, Microrhagus emyi or Malthinus bilineatus), 104 species of hoverflies (Diptera, Syrphidae), 17 In a global framework of sustainable management, species of bats, and the spider Harpactocrates the current economic aims of the owners are to ravastellus which is endemic to the Pyrenees (Lar- obtain an income from timber, provide annual fuel- rieu 2005). Fungi assemblages observed in dry Ses- wood for the owners (about 120 m3), and optimise leria caerulea beech-fir forest are unique in com- the use of the subalpine meadows by allowing live- parison with other European habitats of stock owners from outside the GF, since there Cephalanthero-Fagion (Corriol and Larrieu 2008). amount of livestock belonging to the local forest Because of the wide array of substrata and owners has declined. topo-climates, vascular plants are very diverse.

21 5 500 3500 1000 102 6000 38 3400

5000 230 534 15000 18000

Beech-dominated Wood products Plantations (cleaning, pruning, etc.) Mixed Beech-Fir Livestock (rent of grazing Oak dominated areas) Road network Other broadleaves Hunting Rangers Conifer plantations Livestock (meadow maintenance, pens) Broadleaves plantations Shepherd huts Fig. C 9.3. Forest area per dominant Fig. C 9.4. Mean annual income for Fig. C 9.5. Forest management costs stand type (ha). 2014–2019 (€/yr). – mean expenses for 2014–2019 (€/yr).

302 Some of them are protected at the regional or national levels, such as Cerinthe glabra subsp. pyre- naica, Cystopteris montana or Ramonda myconi. The bryophyte Buxbaumia viridis (fig. C 9.6a) occurs on some large pieces of deadwood in old-growth stands (Larrieu 2005). Cliffs provide nesting sites for the rare birds Eurasian eagle owl (Bubo bubo), peregrine falcon (Falco peregrinus), Egyptian vulture (Neophron percnopterus), and also for rocky-dwelling bats a such as the European free-tailed bat (Tadarida teniotis). The Pyrenean subspecies of capercaillie (Tetrao urogallus subsp. aquitanicus) is found at the upper forest limit (Larrieu 2005). The forest is fully within a ‘Zone naturelle d’in- térêt écologique, faunistique et floristique’ (ZNIEFF; Natural zone of ecological interest, fauna and flora).

Nature conservation

The current management plan (2000–2029) includes expert reports about both flora/habitats and caper- caillie. In order to take into account the chemical b fragility of certain very nutrient-poor soils (Larrieu et al. 2006), a stand (roughly 20 ha) has been set aside. During harvesting, recommendations of spe- cialised scientists for an - and fungi-friendly management (Larrieu et al. 2005, 2008) are taken into account. Even though oak (Quercus petraea, Q. robur) dominated stands have a very low pro- ductivity, no replacement is planned since these stands are used by bats for foraging. A proportion of the very large trees (>70 cm diameter) are retained within harvested stands, and some crowns from harvested trees remain on the ground with- out being cut; however, there is no minimum den- sity or volume of deadwood to be kept in the for- est. Snags are fully conserved; some lying deadwood c items are used for firewood when they are very close to roads, but most of them remain within

Fig. C 9.6. The Green Shield-moss (Buxbaumia viridis) is mainly observed on large downed coniferous deadwood items (a). The Lesser Stag (Dorcus parallelipipe- dus): the adult feeds on sap while the larva is saproxylic (b). The (Lamia textor) is more commonly observed near streams since its saproxylic larva lives mainly in the deadwood of Salix, and Alnus (c). The Porcelain fungus (Oudemansiella mucida) is a saproxylic species living in crown deadwood of beech (d) (Photos: Laurent Larrieu [a–d]).

d 303 How to balance forestry and biodiversity conservation – A view across Europe

Fig. C 9.7. Attractive tourist spots for cavers, hikers and climbers, but also for rare bird species as Eurasian eagle owl (Bubo bubo), peregrine falcon (Falco peregrinus), Egyptian vulture (Neophron percnopterus) (Photo: Laurent Larrieu).

stands. In naturally mixed stands currently domi- a stand where a breeding pair of goshawks (Accipi- nated by beech, silver fir is systematically conserved ter gentilis) were found. Climbing is regulated to in order to increase its proportion. Post-pioneer minimise disturbance to protected cliff-dwelling tree species are promoted since they support spe- birds; areas and periods where climbing is allowed cific biodiversity and they very often have a high are fixed every year in accordance with the bird commercial value. species and the location of their nests. Figure C 9.7 In 2004, a harvesting operation was delayed for shows attractive places for nesting sites but also for several months in order to minimise disturbance in tourists and adventurers.

Fig. C 9.8. Important for recreation and production. The entrance to the forests is controlled by gates and only forest owners can access the area by car (Photo: Laurent Larrieu).

304 C 9 Hèches, France

Recreation belonging to the European network Integrate+ was set up on the property. The council members The GF allows free use of cliffs and caves for climb- were trained to carry out the monitoring and meas- ers and cavers, and also free use of roads and paths urement of the trees. The wood is sold as standing for trekkers. However, forest entrance is controlled timber by the ‘lump sum’ method (i.e. the timber is by a gate and only owners can drive by car through sold in advance before harvesting). the area (fig. C 10.8). Hunting and mushroom har- vesting are reserved for the owners and local peo- Policy ple. Management daily decisions are taken by the pres- ident or by the board (which meets four times a year). Once a year, a meeting gathers all the mem- Strengths and weaknesses bers of the ownership group and the main strategic guidelines are discussed and then approved. Dur- Management ing this meeting, the president also presents the The GF does not generate enough money to pay financial statements. for professional forest management, and therefore marking of trees for logging is done by council Science members; however, none of the council members Since 2000, this property has hosted many ecologi- are professional foresters. In 2017, a marteloscope cal studies focussing on biological conservation and (a 1 ha silvicultural training site in which all trees sustainable management. For many studies, the are numbered, mapped, and recorded; fig. C 9.9) area was one part of a larger study (e.g. Bouget

Fig. C 9.9. The 1 ha-marteloscope was set-up in a beech-fir stand, the dominant stand type on the property (Photo: Laurent Larrieu).

305 How to balance forestry and biodiversity conservation – A view across Europe et al. 2020; Friess et al. 2019; Larrieu et al. 2018; this action would need a change in the old status of Courbaud et al. 2017; Müller et al. 2015; Larrieu the GF that legally prevents the GF stopping collec- and Cabanettes 2012). However, this forest was tion of lying deadwood. Pioneer tree species such sometimes specifically studied for impact of har- as silver (Betula pendula) and aspen (Populus vesting on soil chemistry (Larrieu et al. 2006), on tremula) should be better considered, in view of hoverfly communities (Larrieu et al. 2015), on both their support for biodiversity, although their com- deadwood and tree-related microhabitats amount mercial value is low. Finally, when a stand gets a (Larrieu et al. 2012), or on beetle communities (Brin fully regular structure, some mature trees should et al. 2010). be retained when the stand is being regenerated to Adaptive management is not really imple- provide ecological continuity between the two mented, but the owners have tried to improve the commercial cycles. silvicultural methods following the science, e.g. by allowing part of harvested tree crowns to remain in the stand to increase the amount of deadwood References amount, or by setting aside stands growing on very Bouget, C.; Brin, A.; Larrieu, L., 2020: The use of sentinel nutrient-poor soils. logs to assess host shifts in early beetle colonizers of deadwood under climate- and forestry-induced tree Communication species substitutions. Insect Conservation and Diversity. Since 2001, the property has been used for training https://doi.org/10.1111/icad.12434 Brin, A.; Brustel, H.; Valladares, L.; Larrieu, L., 2010: Contri- courses about pedology, botany, pastoralism, inte- bution à la connaissance des Coléoptères saproxyliques grated forest management. The target audiences des forêts pyrénéennes (3ème note: la forêt de Hèches, are students, forest advisers, forest managers, and Hautes-Pyrénées) [Contribution to the knowledge of also other private landowners. Saproxylic Beetles of the Pyrenean forests]. Bulletin de Nature conservation is not really integrated by la Société Linnéenne de Bordeaux. Tome 145, (N.S.) all the GF’s owners, in accordance with a long tradi- n°38, 4:2010: 397–416. Corriol, G.; Larrieu, L., 2008: Étude mycocoenologique de tional farming use of the area. However, the presi- la hêtraie sèche à Sesleria caerulea (Cephalanthero-Fa- dent and other board members are aware of the gion), des Pyrénées centrales. Documents Mycologiques need to promote more integrated management. XXXIV 135–136: 9–124. The forest management of the GF has been labelled Courbaud, B.; Pupin, C.; Letort, A.; Cabanettes, A.; Larrieu, by the Programme for the Endorsement of Forest L., 2017: Modelling the probability of microhabitat for- Certification (PEFC; certificate 10-21-15). mation on trees using cross-sectional data. Methods in Ecology and Evolution. 8: 1347–1359. https://doi.org/10.1111/2041-210X.12773 Friess, N.; Müller, J.; Abrego, N.; Aramendi, P.; Bässler, C.; Conclusion Bouget, C.; Brin, A.; Bussler, H.; Georgiev, K.; Gil, R.; Gossner, M.; Heilmann-Clausen, J.; Isaacson, G.; Kristin, Owners participating in management decisions or A.; Lachat, T.; Larrieu, L.; Los, S.; Magnanou, E.; practical issues such as tree-marking need to be Maringer, A.; Mergner, U.; Mikolas, M.; Opgenoorth, L.; better trained. The establishment of the martelo- Schmidl, J.; Svoboda, M.; Thorn, S.; Vrezec, A.; Vanderk- scope on the property will help to provide informa- hove, K.; Winter, B.; Wagner, T.; Zapponi, L.; Brandl, R.; Seibold, S., 2019: communities in fungal tion and to train the owners about biodiversi- fruitbodies are weakly structured by climate and bioge- ty-friendly silviculture. ography across European beech forests. Diversity and Financial incentives to retain very large trees Distributions. 25: 783–796. would benefit biodiversity conservation as these https://doi.org/10.1111/ddi.12882 trees play a huge role in biodiversity conservation, Larrieu, L., 2005: Etude de certains aspects de la diversité but landowners often consider them as competi- biologique de la forêt des montagnes particulières de Hèches (Vallée d’Aure, Hautes-Pyrénées), en vue d’une tors for younger and more productive trees. How- gestion sylvicole compatible avec sa conservation. Rap- ever, in France, such financial support only exists in port d’étude. 290 p. N2000 areas. Larrieu, L.; Brustel, H.; Sarthou, J.P., 2005: Quelques prop- The amount of deadwood could be increased, ositions pour la prise en compte des insectes, en partic- e.g. by stopping the harvesting of lying deadwood ulier saproxyliques, dans la gestion quotidienne des as a source of firewood for the owners. However, forêts; 4 p.

306 C 9 Hèches, France

Larrieu, L.; Cabanettes, A., 2012: Species, live status, and diameter are important tree features for diversity and abundance of tree-microhabitats in subnatural mon- tane beech–fir forests. Canadian Journal of Forest Research. 42: 1433–1445. https://doi.org/10.1139/x2012-077 Larrieu, L.; Cabanettes, A.; Delarue, A., 2012: Impact of silviculture on dead wood and on the distribution and frequency of tree microhabitats in montane beech-fir forests of the Pyrenees. European journal of Forest Research. 131: 773–786. https://doi.org/10.1007/s10342-011-0551-z Larrieu, L.; Cabanettes, A.; Sarthou, J.P., 2015: Hoverfly (Diptera: Syrphidae) richness and abundance strongly decrease, in montane beech-fir forest, as stand hetero- geneity decrease. European Journal of Entomology. 112: 755–769. https://doi.org/10.14411/eje.2015.083 Larrieu, L.; Corriol, G., 2008: Biodiversité et gestion dura- ble des forêts. Quelques propositions pour la prise en compte des champignons. 4 p. Larrieu, L.; Gosselin, F.; Archaux, F.; Chevalier, R.; Corriol, G.; Dauffy-Richard, E.; Deconchat, M.; Gosselin, M.; Ladet, S.; Savoie, J.M.; Tillon, L.; Bouget, C., 2018: Cost-efficiency of cross-taxon surrogates in temperate forests. Ecological Indicators. 87: 56–65. https://doi.org/10.1016/j.ecolind.2017.12.044 Larrieu, L.; Nys, C.; Jabiol. B., 2006: Prise en compte de la fragilité chimique des sols forestiers dans les conseils de gestion. Illustration pour une sapinière-hêtraie mon- tagnarde sur roche acide. (Vallée d’Aure, Hautes- Pyrénées) [Consideration of chemical vulnerability of forest soils to inform management counselling. Illustra- tion through a mountain beech/fir stand planted on acid bedrock]. Revue Forestière Française. LVIII: 531– 548. https://doi.org/10.4267/2042/8021 Larrieu, L.; Sajdak, G.; Cabanettes, A.; Drénou, C., 2018: Dépérissement du sapin pectiné: influences du diamè- tre, du gui et des conditions locales. Forêt Entreprise. 240: 6–15. Müller, J.; Brustel, H.; Brin, A.; Bussler, H.; Bouget, C.; Obermaier, E.; Heidinger, I.; Lachat, T.; Förster, B.; Horak, J.; Schlagerhamsky, J.; Köhler, F.; Larrieu, L.; Bense, U.; Isacsson, G.; Zapponi, L.; Gossner, M.M., 2015: Increas- ing temperature may compensate for lower amounts of deadwood in driving richness of saproxylic beetles. Ecography. 38: 499–509. https://doi.org/10.1111/ecog.00908 Pénin, D.; Largier, G., 2000: Evaluation de l’intérêt floris- tique et écologiques de la propriété du GF de Hèches. Conservatoire botanique pyrénéen. Rapport d’exper- tise, 17 p. + annexes. Vallauri, D.; Grel, A.; Granier, E.; Dupouey, J.L., 2012: Les forêts de Cassini. Analyse quantitative et comparaison avec les forêts actuelles [The Cassini’s forests. Quantita- tive analysis and comparison with current forests]. Rap- port WWF/INRA, Marseille, 64 p. + CD.

307