Black Truffle Harvesting in Spanish Forests: Trends, Current Policies and Practices, and Implications on its Sustainability

Abstract

The European black truffle is a mycorrhizal fungus native to Spanish Mediterranean forests. In most Spanish regions it was originally commercially harvested in the second half of the 20th century. Experts agree that wild truffle yields suffered a sharp decline during the 1970s and 1980s. However, official statistics for Spanish harvest are scarce and seemingly conflicting, and little attention has been paid to the regime for the exploitation of truffle-producing forests and its implications on the sustainability of this resource. Trends in harvest from 1969 to 2013 and current harvesting practices were analyzed as a case study, taking into account that Spain is a major truffle producer worldwide, but at the same time truffles have only recently been exploited. The available statistical sources, which include an increasing proportion of cultivated truffles since the mid-1990s, were explored, with estimates from Truffle Harvesters Federation showing higher consistency. Statistical sources were then compared with proxies for wild harvest (rents from truffle leases in public forests) to corroborate time trends in wild harvesting. Results suggest that black truffle production is recovering in recent years thanks to plantations, whereas wild harvest is still declining. The implications of Spanish legal and institutional framework on sustainability of wild truffle use are reviewed. In the current scenario, the decline of wild harvest is likely to continue and eventually make commercial harvesting economically unattractive, thus aggravating sustainability issues. Strengthening of property rights, rationalization of harvesting pressure, forest planning and involvement of public stakeholders are proposed as corrective measures.

Agro-climatic zoning of Spanish forests naturally producing black truffle

“…Only lease agreements for the period 1990-2017 were considered. In most Spain harvesting of wild truffle began between the late 1940s and late 1960s, in all cases with a commercial aim (Garcia-Barreda et al, 2018), so the selected forests continued to provide commercial yields after at least 20 years of intensive harvesting. In addition, information for previous periods is scarce and fragmentary.…”

“…Given the particularities of truffle ecology and harvesting (Garcia-Barreda et al, 2018), we chose to avoid the use of absence data. It is often not possible to reliably corroborate absence points or the factor originating the absence (e. g. unsuitable climate, soil, hosts or forest density, postglacial expansion pattern or intensive harvesting).…”

“…Besides, before climatic data are scarce and irregular in almost all Spain. On the other hand, after 1990 Spanish wild truffle production was sensibly lower likely due to a combination of habitat deterioration, overexploitation and climate change (Büntgen et al, 2012;Garcia-Barreda et al, 2018). 1 Calculated as a non-dimensional ratio between the dry and the humid area in climate diagrams (Walter and Lieth, 1960).…”

“…In recent decades truffle cultivation has become an economic alternative for many regions in southwestern Europe and has spread to other continents (Olivier et al, 2002;Reyna and Garcia-Barreda, 2014). In Spain the widespread exploitation of wild truffle harvests began only in the second half of the 20 th century, with plantations playing an increasingly dominant role in truffle production from the late 1990s (Garcia-Barreda et al, 2018). Spain is home to many of the southernmost natural locations of T. melanosporum, with relatively dry, warm climate and soils with relatively low levels of organic matter (Garcia- Barreda et al, 2007).…”

Nota técnica: Primer éxito en el cultivo de trufa negra en el oeste de la península ibérica y posibilidades de expansión.

“…La trufa negra es la fructificación hipogea del hongo Tuber melanosporum Vittad., el cual vive de forma natural en formaciones boscosas y en simbiosis ectomicorrícica con plantas del género Quercus L. principalmente. Es un producto forestal no maderero muy valorado por su característico e intenso aroma y que, además, puede cultivarse, obteniendo grandes rendimientos y compensando así el descenso de la producción silvestre de las últimas décadas (García-Barreda et al, 2018). España es el segundo productor mundial, después de Francia, con el 27,3% de la producción total que, promediada para los años 2003-2013, ronda las 58 toneladas al año según Reyna y García-Barreda (2014).…”