Wild Plants Potentially Used in Human Food in the Protected Area "Sierra Grande de Hornachos" of Extremadura (Spain)

Abstract

Natura 2000 is a network of protected spaces where the use of natural resources is regulated through the Habitat Directive of the European Union. It is essential for the conservation of biodiversity in Europe, but its social perception must be improved. We present this work as a demonstration case of the potentialities of one of these protected areas in the southwest (SW) Iberian Peninsula. We show an overview of the catalog of native wild plants of the place, which have nutritional and edible properties, having been used in human food by the peasant local population over the last century, and whose consumption trend is being implemented in Europe mainly through the haute cuisine and ecotourism sectors. What is offered here is a study of the case of what kind of positive contribution systematized botanical or ethnobotanical scientific knowledge can make toward encouraging innovative and sustainable rural development initiatives. A total of 145 wild plants that are potentially useful for leading tourism and consumers toward haute cuisine, new gastronomy, enviromentally-friendly recipes, and Natura 2000 Conservation are retrieved. The methodology used for our proposal is based on recent proposals of food product development and Basque Culinary Center initiatives.

1. Introduction

1.1. Plant Resources Global Availability and Potential Use

From approximately 250,000 plant species, it has been estimated that up to 75,000 could be edible [1], and some 7000 are regularly eaten worldwide [2]. Even though the average Western citizen has now access to more species of edible plants than ever, a common household shopping list will not include more than 45 plant species as food supplies. In fact, Western societies tend to use much fewer species than indigenous communities. Regarding wild resources (plant species that grow spontaneously in populations in natural or managed habitats, thriving independently of direct human action, following the definition of [3], 73 plant species are reported to be used in Álava (Spain, [4]), while 66 plant species are reported to be used in Emilia (Italy, [5]), the inhabitants of the Quinling Mountains of Saanxi (China) use up to 185 species [6], and the indigenous peoples of southern Ecuador use up to 354 [7]. The main actor responsible for this steady loss of culinary traditions is globalization [8]; wild edible plants are also often stigmatized due to associations with food shortage and poverty, climatic extreme events, or politically conflictive times ([9] and references therein), leading to the abandonment of wild edible resources and the consequent decline of knowledge in plant uses. What has become increasingly clear is that any approach to biodiversity and landscape conservation must incorporate traditional knowledge in order to achieve success.

1.2. Combined Conservation Trends Focusing on the Natura 2000 Network

In rural communities of southern Spain, a close relationship between biodiversity, local culture, and dialectal diversity has evolved over centuries of history. There is a genuine biocultural heritage [10] that has been specifically developed on a local spatial scale and has been until recent times transmitted through generations. There, significant areas belong to the Natura 2000 Network. This is the organized area for the conservation of biodiversity in Europe. It is regulated through the Habitats Directive of the European Union, which enables compatible development, knowledge, bioeconomy, and innovation [11]. However, sometimes, the measures proposed by the environmental organisms are seen by the local population with suspicion or rejection, and they are challenged [12]. The problem has worried the European authorities to the point of having implemented specific action programs aimed at improving its social perception [13]. Most are oriented to new trends and development opportunities to favor biodiversity and Natura 2000 Network acceptance.

1.3. The Particular Case of the Sierra Grande de Hornachos: Ecological and Cultural Relevance

Hornachos is a small town (3777 inhabitants) [14] of the central Badajoz province (Extremadura) in the southwest of the Iberian Peninsula that has this problematic. It provides an optimal study case for biocultural heritage whose record and divulgation is timely. In addition to this, there is a sociological reality in the territory of unpopularity related to the Natura 2000 Network. In this framework, we are actually carrying out a project supported by the European Union and the regional government. It is intended in the medium term to solve real problems of rejection and blockage that have occurred in the past. An SAC and SPA (Special Area for Conservation and Special Protection Area for Birds) have been developed in the “Sierra Grande de Hornachos” within the Natura 2000 Network [15]. Its forests and thickets represent an ideal environment for the life of abundant Mediterranean wild fauna of high value with elements such as the griffon vulture, the golden eagle, and more than 220 species of vertebrates. There is the cartography of the predominance of holm oaks in flat areas, hillsides, and foothills; of cork oaks in shady and watercourses; of mixed forest; of wild olive trees; of summit junipers; and of Nerium oleander (adelfares) and Flueggea tinctoria (tamujares) in the riparian vegetation. Surprisingly, the flora has been much less inventaried, and no specific floristic catalog of the area has been published to date. For ethnobotanical studies, there are also no specific systematized works, despite the potential of the place. It has a rich historical past that includes a mixture of cultures, such as Christian, Jewish, and Muslim. This circumstance has produced a strong imprint in the agriculture of the area. It influenced the maintenance of agroecosystems, including many activities related to nature, hunting, fishing, medicine, gastronomy, and even traditional crafts, which are as interesting as those from Andalucía [16].

1.4. Local Traditional Knowledge on Food Plants and Resource Management at Sierra Grande de Hornachos

In this region, as well as in others of the Mediterrenean [17], economic marginality, historical factors, and recurrent political crises in old times forced its inhabitants to make the most out of the wild resources found in the vicinity of their settlement. However, over the last decades, the development of agriculture and the globalization phenomena have led to the progressive abandonment of wild edible resources [9,17], and nowadays, it is still a rich bio-heritage that holds value.

Taking into consideration that the regional flora of Extremadura has 1938 species [18] and that the “Sierra Grande de Hornachos” comprises 12,469 ha of well-conserved Mediterranean vegetation units, its floristic resources were expected to be interesting. In a first aproximation, a list that did not reach 50 species was the only published result [19], featuring threatened plants such as Lavatera triloba, Erodium mouretii, Orchis italica and Ophrys fusca subsp. dyris as standouts. The complete floristic inventory of the area was approached by our team in 2016/17 Project IB16003 with the expectation of finding at least 400 species. We made field prospections, and to date, 1301 taxa make up the checklist of the wild vascular plants of Sierra Grande de Hornachos, according to our campaigns and investigations. This systematical biodiversity information (of 1301 taxa) can be crossed with another source (database) that is not open access, but is available in the Ministry of the Environment of Spain: The Spanish Inventory of Traditional Knowledge Relating to Biodiversity. Doing this, all of the vegetal resources can be studied and presented to the local inhabitants of the region as possibilities for the development and progress toward a sustainable society of 21st century. The real challenge relating to the conservation of rural areas and phytodiversity in Europe is to find new trends and opportunities for plants and people. That seems to be the most sucessful way to provide social support for the Natura 2000 Network. This is the main focus of our work. Constructing the catalog of the wild plants of the area, we can look for the uses of these species and explore their possibilities. We can study how they were employed in other places in the country. This means that they can effectively be also utilized in the same way. Thus, the traditional used and conserved knowledge will drive innovative applications in the area. In summary, a positive view of the sustainable exploitation of natural resources in the Natura 2000 Network can promote a friendly face of conservation measures. For this reason, it is important to explore this method of management.

1.5. Innovation for Conservation: Wild Gathering, Agro-Tourism, Gourmet Foods, and Local Memories

New initiatives are starting in Europe. Agro-tourism is rapidly increasing its popularity through urban Western societies, ultimately enabling the survival of traditional knowledge and the gathering of wild plants itself [20]. Nevertheless, a renaissance of interest in traditional plant knowledge is beginning. Gathering wild edible plants has become popular as a means of enjoying outdoor contact with nature and granting alternative, high-end culinary experiences [9]. Wild plant consumption is not unfainly seen as “an occupation for the poor, which increased during times of bad crops and famine”, but also a fashionable part of 21^st century haute cuisine [17]. It is even increasingly seen as a form of reaffirming cultural identity, sophistication, and commitment to the community. In brief, innovative strategies suggested for natural resources are excellent tools for promoting the culture of biological conservation among social sectors, and hopefully serve to mitigate local rejects to Natura 2000 regulations.

In that framework and with the underlying characteristics of the case of Hornachos, we state the specific objectives for this work.

1.6. Objectives

The objective of this work is to record the threatened biocultural heritage of a Natura 2000 area (Hornachos) on wild edible plants with the double purpose of preserving it and setting the basis for a valorization and divulgation program focused on the local and visiting population.

2. Materials and Methods

• The database of the Spanish Inventory of Traditional Knowledge Relating to Biodiversity (IECTB) [21,22,23,24] comprising of 3156 record (taxa) was taken as a basis. To date, it is not yet open access. So, permission to consult it was formally required by the authors (J. Blanco-Salas) and allowed by the IECTB national coordinator (M. Pardo de Santayana).
  • IECTB is the Inventory of Traditional Knowledge that has been published in Spain but dispersed in a difficult literature. The realization of this inventory arose from a legislative requirement (Article 70 of Law 42/2007, of December 13, the Natural Heritage and Biodiversity of Spain). In this inventory, the preparation of plants for food uses is written in the same way as it has been reported from local informants.
• In parallel, our research group created a database of Hornachos plants. Basic information was taken from the Global Biodiversity Information Facility (GBIF) [25], the open-access program ANTHOS [26], and the Herbarium UNEX (University of Extremadura) collections.
  • GBIF [25] stands for the Global Biodiversity Information Facility. It is an international network and research infrastructure funded by the world's governments that is aimed at providing anyone, anywhere, open access to data about all types of life on Earth.
  • ANTHOS [26] is an open-access program that was developed to divulge and show society information about the biodiversity of Spanish plants on the Internet. The initiative was born under the umbrella of the Flora Iberica research project (Ministry of Agriculture, Food, and the Environment) and the Royal Botanical Garden of Madrid, Spain.
  • UNEX Herbarium is the herbarium of the University of Extremadura, which was formed by 36,451 specimens of vascular plants whose main origin is the autonomous region of Extremadura (Spain) and Portugal. Here is the place where we included the voucher speciments of our field collections.
• The Hornachos list finally resulted in 1301 plants. We looked for 1301 names in the IECTB Inventory official database, and 834 matched (Figure 1). This means that we firstly had 834 useful taxa and 1301−834 = 467 taxa without use.
• The IECTB inventory database information compiled in “one file for plant” format has not yet been completely published. Of the 834 useful Hornachos plants included in the IECTB, to date, the IECTB has made information on 278 species available in published books [21,22,23,24] (the remainder of the 834 species will be published in the future, when the IECTB project is finished). Of these 278 useful Hornachos plants, 145 species were edible plants. These names of edible plants were listed.
• A provisional database of the edible plants of Hornachos was built, with 145 records (corresponding to the provisional 145 edible plants in Hornachos).
  • Botanical nomenclature was adapted to the Angiosperm Phylogeny Group (APG) IV System [27] and included vernacular names.
  • Part of the plant used (upon the information taken from the IECTB).
  • Subcategory of food use. The ones considered were: A = Vegetables; B = Roots, bulbs, tubers, and rhizomes; C = Sweet fruits; D = Dry and oleaginous fruits; E = Cereals and pseudocereals; F = Fat; G = Alcoholic drinks; H = Non-alcoholic drinks; I = Condiments; J = Sugars and sweeteners; K = Candies and chewing; L = Other food uses. They are the same as considered by the IECTB. The information for filling the corresponding fields was literally transferred from the IECTB.
  • Preparation. It was filled upon the following classification: 1 = Soups; 2 = “gofio” (= roasted cereal stirred into liquid); 3 = Broths and purees; 4 = Omelettes; 5 = Cakes; 6 = Rices; 7 = Salads; 8 = Cold vegetable soups; 9 = Pies/Patties; 10 =Potages; 11 = Stews; 12 = Scrambled; 13 = Sautéed/boiled/toasted; 14 = Milky; 15 = Fried/breaded; 16 = Sauces; 17 = Oil; 18 = Vinegar; 19 = Renner; 20 = Preservative; 21 = Dressings/condiments; 22 = Flour; 23 = Sugar; 24 = Desserts; 25 = Ice creams; 26 = Sorbets; 27 = Cakes/Cakes; 28 = Sweet; 29 = Jams; 30 = Marmalades; 31 = Jellies; 32 = To the natural; 33 = Brine; 34 = Pickles; 35 = In syrup; 36 = In alcohol; 37 = Wines; 38 = Liquors; 39 = Syrups for cocktails; 40 = Juices; 41 = Brandies; 42 = Infusions; 43 = Coffee/tea; 44 = Diluted syrups. This classification is based on that of Bertrand [28]. We assigned the information about preparation, which was recorded in IECTB format, to the corresponding culinary categories of Bertrand.
• Finally, tables and graphs were made in order to facilitate discussing the results.

3. Results

The constructed database had a total of 145 records. For each record, we considered the nomenclatural field (family, scientific, and vernacular), 15 sub-categories of food uses according to the IECTB, 42 Bertrand food classifications, and 22 possible parts of the the plant used. The total matrix of managed results included 145 × 3 × 15 × 42 × 22 = 6,029,100 possible raw data. The raw data results are summarized in

Table A1. Catalog of edible plants present in the protected area " Sierra Grande de Hornachos”.

Family	Scientific Name	Vernacular Name	PP	Subc	Pr	CL F
Adoxaceae	Sambucus nigra L.	Saúco	I, Fr	A, C, G, H	a, b	4, 24, 29, 30, 33, 37, 38, 40
	Viburnum tinus L.	Durillo	L	I	b	21
Amaranthaceae	Chenopodium album L.	Cenizo	Wp, R	A, B	a, b	1, 4, 6, 7, 8, 10, 11, 12, 22
	Chenopodium murale L.	Cenizo	Wp	A	c	7
Amaryllidaceae	Narcissus bulbocodium L. *	Campanitas	B, F	B, K	b	n.d.
	Allium ampeloprasum L.	Ajo porro	Wp, B, Bp	B, I	a, b	1, 4, 6, 7, 8, 11, 12, 13, 14, 15, 21
	Allium roseum L.	Ajo porro	L, B	A, B, I	a, b	2, 7, 10, 11, 21, 24
Anacardiaceae	Pistacia lentiscus L.	Lentisco	Ap, Wp, L, Sv	G, I, K, L	b	20, 21, 38
Apiaceae	Apium graveolens L.	Apio	Wp	A	a, b	n.d.
	Apium nodiflorum (L.) Lag.	Berra	St, Bs	A	a, b	2, 7, 8, 11
	Foeniculum vulgare Mill.	Hinojo	L, Bs, I, St, Wp, S, Fr	A, G, H, I, K, L	a, b	1, 4, 6, 7, 9, 10, 11, 13, 21, 37, 38, 40, 41, 42
	Scandix australis L.	Quijones	Wp, Ap	A, G, H, I	a, b	11, 21, 38, 40, 41
	Scandix pecten-veneris L.	Alfileres	L, Fr	A	a, b	11
	Thapsia villosa L. *	Cañaheja	R, Wp	B, G, I	a, b	21, 38
Apocynaceae	Vinca difformis Pourr. *	Alcandorea	F	K	b	n.d.
Araceae	Arisarum simorrhinum Dur. *	Candil	Tu	B	c	2
	Arum italicum Mill. *	Aro	Tu	B	a	5, 10, 14
Araliaceae	Hedera helix L. *	Hiedra	St	A	c	n.d.
Aristolochiaceae	Aristolochia paucinervis Pomel *	Candil	St	A	a	11
	Aristolochia pistolochia L. *	Candil	St	A	a	11, 12
Asparagaceae	Ruscus aculeatus L.	Rusco	Bs, St	A, I	a, b	4, 21, 24
	Urginea maritima (L.) Baker *	Cebolla	L	I	b	20
Asphodelaceae	Asphodelus aestivus Brot.	Cebollino	L, Bs, Tu	A, B	a	11
	Asphodelus albus Mill.	Gamón	L, Bs, Tu	A, B	a	11
	Asphodelus fistulosus L.	Cebollino	L, Bs, Tu	A, B	a	11
	Asphodelus ramosus L.	Gamón	L, Bs, Tu	A, B	a	11
Aspleniaceae	Asplenium ceterach L.	Doradilla	Wp	G	b	38
Asteraceae	Achillea ageratum L.	Árnica	Wp	A, H	c	44
	Anacyclus clavatus (Desf.) Pers.	Magarza	L, Bs	A	c	n.d.
	Andryala integrifolia L.	Árnica	L, St	A	a, b	7
	Andryala laxiflora DC.	Árnica	L, St	A	b	7
	Andryala ragusina L.	Ajonje	St, Sv	K	b	n.d.
	Anthemis cotula L.	Magarza	Wp	G	c	38
	Bellis perennis L.	Margarita	L, F	A, K	b	7
	Calendula arvensis L.	Caléndula	Bs, F	A	a, b	11
	Carthamus lanatus L.	Cardo	L, F	A, I	a, b	7, 10, 11, 19
	Chamaemelum fuscatum (Brot.) Vasc.	Magarza	F	H	a	42
	Chamaemelum nobile (L.) All.	Manzanilla	I, F	G, H	a, b	38, 42
	Chondrilla juncea L.	Ajonjera	L, St, Wp, Sv	A, K	a, b	1, 7, 11
	Cichorium intybus L.	Achicoria	L, Bs, R, F	A, H, K	a, b	1, 7, 9, 11, 12, 13, 15, 43
	Crepis capillaris (L.) Wallr.	Almirón	Wp	A	c	n.d.
	Crepis foetida L.	Almirón		A	c	n.d.
	Crepis vesicaria subsp haenseleri (Boiss. ex DC.) P.D.Sell	Achicoria	L	A	a,b	4, 7, 10, 11
	Cynara cardunculus L.	Cardo	L, St, F, Wp, Pn	A, I, K	a, b	6, 7, 10, 11, 15, 19, 24, 33
	Cynara humilis L.	Alcachofa	I, F	A, L	a, b	19
	Dittrichia graveolens (L.) Greuter	Hierba matapulgas	Ap	I	a	21
	Dittrichia viscosa (L.) Greuter	Olivarda fina	I	G	b	38
	Galactites tomentosa Moench	Cardo	St	A	c	n.d.
	Helichrysum stoechas (L.) Moech	Manzanilla	Pe, F, Ap	G, H, L	a	38, 43
	Mantisalca salmantica (L.) Briq. & Cavillier	Escoba	L, St	A	a, b	7, 10, 11, 12
	Matricaria chamomilla L.	Manzanilla	I, F	G, H	a, b	40, 42
	Reichardia intermedia (Schultz Bip) Samp.	Lechuguilla		A	a, b	7, 13, 15, 24
	Scolymus hispanicus L.	Cardillo	L, St, R, F	A, I	a	4, 11, 12, 13, 15, 19, 20, 21, 32
	Scorzonera angustifolia L.	Teta de vaca	L, Pf, F	A, K	a, b	7, 11
	Scorzonera hispanica L.	Alcarcionera	Bl, R	K	b
	Scorzonera laciniata L.	Berbaja	L, F, R, St, F	A, B, K	a, b	4, 7, 11, 13
	Silybum marianum (L.) Gaertner	Cardo mariano	Wp, S, Fr	A, I, K	a, b	7, 10, 11, 13, 15, 19
	Sonchus asper (L.) Hill	Cerraja	L	A	a, b	6, 7, 9, 13, 15
	Sonchus oleraceus L.	Cerraja	L, Bs, R	A,B	a, b	2, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 24
	Sonchus tenerrimus L.	Cerraja	L	A	a, b	5, 7
	Tragopogon porrifolius L.	Teta de vaca	L, I, R	A, K	a, b	7, 11
	Urospermum picroides (L.) Scop. ex F.W. Schmidt	Cerrajón	L, Bs, R	A, B, H	a, b	7, 9, 13 ,15
	Xanthium spinosum L.	Cadillo	Wp	G	c	38
Boraginaceae	Borago officinalis L.	Borraja	L, St, F	A, K	a, b	4, 7, 11, 12, 15, 24
Brassicaceae	Capsella bursa-pastoris (L.) Medik.	Bolsa de pastor	L, Ap, Fr	A, G, K	a, b	1, 12, 38
	Eruca vesicaria (L.) Cav.	Oruga	L, Bs, S	A, D, I	a, b	4, 7, 8, 10, 11, 15, 21
	Rapistrum rugosum (L.) All.	Ravaniza	L	A	a	6, 10, 11
	Sisymbrium irio L.	Rabaniza	L	A	a	11
	Sisymbrium orientale L.	Tamarilla		A	a, b	6, 8
Campanulaceae	Campanula rapunculus L.	Vara de San José	Bs, R, Fr	A,B,G	a,b	7,13,38
Caprifoliaceae	Lonicera etrusca G. Santi	Madreselva	F	K	b	n.d.
	Lonicera implexa Aiton	Madreselva	F, Ap	G, K	b	38
	Lonicera periclymenum subsp hispanica (Boiss & Reuter) Nyman	Madreselva	I, F	G, K	c	38
Caryophyllaceae	Herniaria cinerea DC.	Arenaria	Wp	G	c	38
	Herniaria glabra L.	Arenaria	Wp	G	c	38
	Herniaria lusitanica Chaudhri	Arenaria	Wp	G	c	38
	Herniaria scabrida Boiss	Arenaria	Wp	G	c	38
	Silene vulgaris (Moench) Garcke	Colleja	L, St, R, Wp	A, B, L	a, b	4, 6, 7, 9, 10, 11, 12, 15, 34
	Stellaria media (L.) Vill.	Pamplina	L	A	a, b	7, 11
Cistaceae	Cistus albidus L.	Estepa	S	D	c	n.d.
	Cistus ladanifer L.	Jara	F, S, Sv	A, D, K	b	n.d.
Crassulaceae	Sedum album L.	Arroz	L	A, K	b	33, 34
	Umbilicus gaditanus Boiss.	Campanitas		A	c	n.d.
	Umbilicus rupestris (Salisb.) Dandy	Ombligo de Venus	L	A	a, b	7, 11
Cucurbitaceae	Bryonia dioica Jacq.	Nueza	Bs, Z	A	a, b	1, 4, 7, 8, 11, 12
Cyperaceae	Scirpoides holoschoenus (L.) Soják	Junco	S, Bl	E, K	a, b	2, 22
Cytinaceae	Cytinus hypocistis (L.) L.	Colmenita	F	K	b	13, 15
Dennstaedtiaceae	Pteridium aquilinum (L.) Kuhn	Helecho	Rz, L	B, K	a, b	5, 22
Dioscoraceae	Tamus communis L.	Espárrago	Bs	A	a, b	4, 11, 13, 15
Equisetaceae	Equisetum ramosissimum Desf.	Cola de caballo	Bs, St	A, G	a, b	15, 38
Ericaceae	Arbutus unedo L.	Madroño	Fr, L, St, Ba	C, G, I, K	a, b	21, 24, 29, 30, 37, 38, 41
Fabaceae	Bituminaria bituminosa (L) Stirton	Angelota	F	K	b	n.d.
	Lygos sphaerocarpa (L.) Boiss	Retama	St, Bs, L	I, L	b	20
	Medicago sativa L.	Alfalfa	Bs, Wp	A, G, H	a	1, 4, 6, 7, 12, 13, 15, 38, 43
	Onobrychis humilis (L.) G. López	Carretilla	F	K	b	n.d.
	Spartium junceum L.	Retama	F	G	c	38
Fagaceae	Quercus rotundifolia Lam.	Encina	Fr	D, F, G, H	a, b	5, 13, 17, 22, 24, 27, 38, 40, 43
	Quercus suber L.	Alcornoque	Fr	D	a	13
Gentianaceae	Centaurium erythraea subsp grandiflorum (Biv) Melderis	Centaura	Wp	G	c	38
	Centaurium maritimum (L.) Fritsch	Centaura	Wp	G	c	38
	Centaurium pulchellum (Swartz) Druce	Centaura	Wp	G	c	38
Hypericaceae	Hypericum perforatum L.	Hipérico	F, Ap	G, H, K	a, b	38, 42
Lamiaceae	Calamintha nepeta (L.) Savi	Hierba nieta	Wp, Ap, F	G, H, I, L	a	21, 38, 43
	Marrubium vulgare L.	Marrubio	F. Ap	G	c	38
	Melissa officinalis subsp altissima (Sibth & Sm) Arcangeli	Toronjil	Fr, Ap, L, F	G, H, I	a, b	21, 37, 38, 42
	Mentha pulegium L.	Poleo	F, Ap, L	G, H, I	a	21, 38, 42
	Origanum vulgare subsp. vires (Hoffmanns. & Link) Bonnier & Layens	Orégano	Wp, Ap, F	G, H, I	a, b	21, 37, 38, 42
	Phlomis lychnitis L.	Candilera	L, F	H, K	a, b	42, 43
	Phlomis purpurea L.	Matagallos	L	K	b
	Rosmarinus officinalis L.	Romero	Bs, L, St, F	G, I, K	b	17, 18, 21, 37, 38
	Sideritis hirsuta L.	Rabo de gato	F, Ap	G, H	a	38, 42
	Thymus mastichina (L.) L.	Mejorana	F, Ap	G, I	b	21, 38
Malvaceae	Malva sylvestris L.	Malva	L, P, F, Fr	A, G, H, K	a, b	7, 11, 15, 38, 40, 42
Myrtaceae	Myrtus communis L.	Arrayán	Fr, F, Ap, L	C, G, H, I	a, b	20, 21, 25, 30, 37, 38
Oleaceae	Olea europaea L.	Acebuche	Fr	D	b	17, 33
	Phillyrea angustifolia L.	Labiérnago	Wp	I	a	20
Oxalidaceae	Oxalis corniculata L.	Trébol	L	A	c	n.d.
Papaveraceae	Papaver dubium L.	Amapola	L, P	A	a, b	6, 7, 27
	Papaver hybridum L.	Amapola	L, St	A	a, b	7, 10, 11
	Papaver pinnatifidum Moris	Amapola	L	A	a, b	6, 7, 27
	Papaver rhoeas var. rhoeas L.	Amapola	L, St, P, F, S	A, G, I	a, b	4, 7, 8, 10, 11, 12, 13, 15, 21, 38
	Roemeria hybrida (L.) DC.	Amapola morada	Bs	A	a, b	4, 7, 10, 12, 13
Pinaceae	Pinus pinea L.	Pino piñonero	S, Fr	D, G, I	a, b	11, 20, 21, 24, 34, 38
Plantaginaceae	Digitalis purpurea subsp toletana (Font Quer) Hinz *	Digital	F	K	b	n.d.
	Digitalis thapsi L. *	Biloria	F	K	b	n.d.
	Veronica anagallis-aquatica L.	Berro	L, St	A, K	a, b	7
Poaceae	Arundo donax L.	Caña	St, Bl	I, K	b	20, 21
	Cynodon dactylon (L.) Pers.	Grama	Rz, Wp	B, G, H, K	a, b	13, 22, 38, 40, 42
	Elymus repens (L.) Gould	Grama	Rz	B	a	4, 22
Polygonaceae	Rumex pulcher L.	Romaza	L, Ap	A, H	a	4, 6, 7, 10, 13, 15, 40, 43
Portulacaceae	Montia fontana subsp. amporitana Sennen	Pamplina	L, St	A	b	7
	Portulaca oleracea L.	Verdolaga	L, St, Bs	A	a, b	4, 7, 10, 11, 15, 34
Rosaceae	Agrimonia eupatoria L.	Agrimonia	Wp	G	c	38
	Crataegus monogyna Jacq.	Espino albar	L, St, Bs, Fr, S	A, C, G, H	a, b	30, 32, 41, 43
	Rubus ulmifolius Schott	Zarzamora	L, Bs, F, Fr, A	A, C, G, H, K	a, b	4, 13, 24, 30, 38, 40
Rutaceae	Ruta angustifolia Pers.	Ruda	Wp, L, F, S	G, H, I	b	4, 12, 17, 18, 21, 38, 40
	Ruta montana L.	Ruda	Wp, L, F, S	G, H, I	b	4, 12, 17, 18, 21, 38, 40
Smilaceae	Smilax aspera var. altissima Moris & De Not	Zarzaparrilla	Bs, R	A, G, H	a, b	12, 38, 40, 44
Solanaceae	*Solanum nigrum L.	Hierba mora		C	b	n.d.
Ulmaceae	Celtis australis L.	Almez	Fr	C, G, J	b	23, 38
	Ulmus minor Miller	Olmo	L, Bs, F	A, K	b	n.d.
Urticaceae	Urtica dioica L.	Ortiga	Bs, Wp	A, G	a, b	1, 3, 4, 7, 11, 12, 13, 38
	Urtica membranacea Poiret	Ortiga	L, St	A	a	3, 4, 7, 13
	Urtica urens L.	Ortiga	L, St, Wp	A, G	a	1, 4, 7, 10, 11, 12, 13, 15, 24, 38
Valerianaceae	Valerianella microcarpa Desv.	Canónigo	L	A	c	7

PP = Parts of the used plant (BL = Base of leaf/stem; Bp = Base of the pseudostem; Bs = Tender shoots; B = Bulb; Ba = Bark; F = Flowers; Fr = Fruits; L = Leaves; I = Inflorescence; Ap = Aerial part; Fp = Floral peduncle; Pn = “Penca”; P = Petals; Wp = Whole plant; R = Root; Rz = Rhizome; Sv = Sap/resin/exudate/latex; S = Seeds; St = Stems; Tu = Tubers; Z = tendrils). Subc = Subcategories of food uses proposed by the Spanish Inventory of Traditional Knowledge Relating to Biodiversity (A = Vegetables; B = Roots, bulbs, tubers, and rhizomes; C = Sweet fruits; D = Dry and oleaginosus fruits; E = Cereals and pseudocereals; F = Fat; G = Alcoholic drinks; H = Non-alcoholic drinks; I = Condiments; J = Sugars and sweeteners; K = Candies and chewing; L = Other food uses); Pr = Preparation (a = cooked, b = raw, c = unknown); Cl F = Classification of foods according to Bertrand (2015) (1 = Soups; 2 = “Gofio” (= roasted cereal stirred into liquid); 3 = Broths and purees; 4 = Omelettes; 5 = Cakes; 6 = Rices; 7 = Salads; 8 = Cold vegetable soups; 9 = Pies/Patties; 10 = Potages; 11 = Stews; 12 = Scrambled; 13 = Sautéed/boiled/toasted; 14 = Milky; 15 = Fried/breaded; 16 = Sauces; 17 = Oil; 18 = Vinegar; 19 = Renner; 20 = Preservative; 21 = Dressings/condiments; 22 = Flour; 23 = Sugar; 24 = Desserts; 25 = Ice creams; 26 = Sorbets; 27 = Cakes/Cakes; 28 = Sweet; 29 = Jams; 30 = Marmalades; 31 = Jellies; 32 = To the natural; 33 = Brine; 34 = Pickles; 35 = In syrup; 36 = In alcohol; 37 = Wines; 38 = Liquors; 39 = Syrups for cocktails; 40 = Juices; 41 = Brandies; 42 = Infusions; 43 = Coffee/tea; 44 = Diluted syrups). * Toxic plants. n.d. = no data.

of Appendix A, and the corresponding boxes of Appendix B (Box A1, Box A2, Box A3, Box A4, Box A5, Box A6, Box A7 and Box A8). The resulting 145 species belong to 49 families. Asteraceae is the best represented, with 25 different vegetables, and Lamiaceae stands out for the preparation of alcoholic and non-alcoholic drinks, as well as condiments. Figure 2 summarizes the diversity of uses among the taxonomic groups’ plant uses, which covered up to 12 subcategories of the IECTB, mostly involving brewing and the aromatization of beverages (alcoholic, 51 species, and non-alcoholic, 28 species). Up to 39 species were used as a form of “wild candy”, being picked and chewed as mere entertainment. In the following paragraphs, we discuss the scope of the applications found.

4. Discussion

4.1. Hornachos Natura 2000 Area and Wild Edible Plants: Diversity and General Possibilities

The diversity of edible plants in the Hornachos community catalogued to date is high in comparison with other territories of Europe. It is more than double the number of edible plants used in similar but more urbane environments of the Basque Country (northern Spain [4]) or Emilia (central Italy [5]) and is approaching figures that have been published for human settlements in rural Asia [6]. However, it is still far from those that have been published for the indigenous communities of South America [7]. Apparently, the rich biocultural heritage of Hornachos is still well preserved. This can be explained by the overall lower level of industrialization of Extremadura in comparison with the more developed areas of the country, where contact with nature is much lower, causing the progressive demise of traditional knowledge.

Asteraceae is the most useful family of our catalogue, but this is also one of the three floristically richest families of the regional flora [18]. As in other Mediterranean countries (see a compilation in [9]), the diversity of wild greens correlates with the presence of bitter, pungent, or acrid secondary metabolites that allow for a variety of nuances in the perception of taste. Another nutritional aspect that has been studied recently is the influence of micronutrients in the correct performance of many metabolic processes, even at the prenatal stage [29]. Experimental studies on women have demonstrated the influence and significance of a wild vegetable diet in folate levels, and similar nutritional parameters [30] and specific reviews have focused on the adolescents of developed and underdeveloped countries. [31] Traditional indigenous foods have been studied to evaluate their levels of micronutrients [32], and the suitability of wild vegetables for alleviating human dietary deficiencies has been addressed [33]. Specific studies of plants that have been traditionally consumed in Spain [34] have also been made.

In addition to this, previous studies in the field of haute cuisine have been published on the possibilities of innovation in this field [35,36,37,38]. In Northern Europe [39,40], interesting new design initiatives have been developed related to high-level gastronomy [41,42,43]. Important professionals of the sector with recognized international prestige have proposed cooking with wild plants [28]. The avant-garde cuisine has been linked to the world of art through the creative universe of great chefs from southern Europe such as Ferrán Adriá, El Bulli, and Mugaritz. Specialized official universities have also become subjects, such as the Basque Culinary Centre in Mondragón (Spain) [44]. Following the artistic concept of Chinese cuisine [45], the model has become directed toward the elaboration of dishes [46,47] that are a mixture of art and science. Wild biodiversity has started to be considered as an interesting resource for the development of new gastronomic and edible products [48,49]. Ethnobotany and the study and cataloguing of traditional knowledge by the local population constitute an important resource for implementing new food product development strategies [50].

Figure 3 shows the number of species of our study, which can be organized according to the different culinary uses of Bertrand classification [28], based on the raw data compiled in Table A1. Apart from the individual potential of each species, we consider that the examples that we expose next have an added value.

4.2. Wild Edible Plants: Innovative Gastronomy and Healthy Promotion

First courses and dishes can be creatively improved by the incorporation of many of the above-mentioned examples. Table A1 summarizes which vegetables have been experimented by traditional cooks, to prepare all kind of soups, broths, purees, omelettes, pies, patties, and salt cakes. The most common way of using the plants of our catalogue has been in stewing rices or potages, or adding them to salads. There is an immense arsenal of creativity at the disposal of the talent of the future professionals of haute cuisine. In Table A1, the species assigned to the Bertrand classification numbers 7, 10, and 11 are direct examples (last column). Another interesting new way of exploring haute cuisine is the new formulation of fried, breaded, sautéed, boiled, or toasted culinary preparations made out of the plants that we have assigned in Table A1 as belonging to the Bertrand classification numbers 13 and 15.

Soups can be made with Chenopodium or Urtica, which also carry Allium or Foeniculum, for example. The first one provides minerals, fiber, vitamins, and essential fatty acids that enhance the sensory and functional value of the food [51]. The latter is especially significant in the last two cases. Omelettes recipes can be based on Crepis vesicaria subsp. haenseleri, Scorzonera laciniata, Sonchus oleraceus, Borago officinalis, or Eruca vesicaria. There is even a tradition of using the young shoots of Tamus communis and Brionia dioica as a substitute for Asparagus for this same purpouse. Their particularly bitter taste makes them peculiar, and precaution about the preparation must be taken in account in order to avoid the unwanted effects that the bibliography describes [17]. Scrambled Capsella bursa-pastoris and cold vegetable soups (gazpachos) where Sisymbrium orientale or Allium ampeloprasum are added have a bromatological explanation. These plants are rich in sulfur components belonging to the glucosinolate group (for the Brassicaceae) and the non-proteic amino acids (for the species of Allium).

In any case, they are very odorous molecules with a high biological activity [52]. In a similar direction, the use of other species of Allium or elements of the mentioned familiy (e.g., Rapistrum rugosum, Sisymbrium irio), as proposed in Table A1, for the recipes for stew presentations, is worthwhile because it enables the incorporation of the phyochemical variability of the systematics to the cuisine. For the preparation of rice, Sisymbrium orientale is recommended. The same can be said about Sonchus asper, which has an excelent nutritional profile, being very rich in fiber and ω-3 acids [53]. We emphasize as well the singularity of the proposal of using previously cooked Cytinus hypocistis because it is a healthy and antioxidant food, but it is also very astringent [54]. Salad is a very fashionable group for gourmets in agro-tourism. New developments can be made by taking any of the plants that are codified with the number seven from from Table A1. Some of them (e.g., Apium, Chenopodium, Chondrilla juncea, Bellis perennis, Montia fontana, Silene vulgaris, Stellaria media, Sonchus tenerrimus, Tragopogon porrifolius, Umbilicus rupestris, Valerianella microcarpa, and Veronica anagallis-aquatica) are already entering the high Spanish hotel industry and occupying small selectede market niches. They have organoleptic and nutritional values [54] mainly as antioxidants [55], which is very interesting.

Another group that is worthy of mention for its variability is the drinks category. We have found a large list of plants that remain at the moment underexploited in the Hornachos local area, having a great potential in the industry of liquors, spirits, and soft drinks. Table A1 summarizes the potentialities of the flora of this Natura 2000 area in this sector (Bertrand classification numbers 36 to 44). Our proposal can really be transferred to land, because Hornachos is situated next to Tierra de Barros (Badajoz), which is an active vinegrowing district, with a developed liqueur industry. There is a possibility of making vinegar with rosemary oil and brandy with a few plants that could be explored. They are Sambucus nigra, Foeniculum vulgare, and Arbutus unedo, respectively, which are very rich [56,57,58] in phenolics derivatives. Diluted syrups with Achillea ageratum and Smilax aspera are surely based on the chemical composition of these two plants, for they have esteroidic and saponine components [59] that favor those sorts of viscous formulations. Table A1 also shows the infusions that could be prepared with the autochthonous elements of the territory. In the case of chamomiles, which are recommended for their stomachic and digestive properties, the different species (Chamaemelum nobile, Chamaemelum fuscatum, Matricaria chamomilla, and Heychrysum stoechas) provide different qualities and let the consumer choose according to their individual preferences. This is related to the chemical profile of the essential oil, which has been characterized by chromatography [60,61]. Other digestive genera include Mentha, Origanum, Sideritis, and Thymus [62]. The antiinflamatory profile of Phlomis [63] and Malva [64] or the sedative of other cases such as Melissa, Hypericum, or Crataegus [64] are very interesting from the nutraceutic point of view.

The Confectionery and Preserves groups have discrete representations (see Figure 3), which do not detract from the importance of particular species. The sweetening power of Celtis australis would be worth investigating for its improvement and exploitation of low-calorie programs, which are in the interest of the overweight public [65]. Others can be objects of creativity, such as ice creams, sorbets, or marmalades made out of the mature fruits of Myrtus communis, which have excellent antioxidant properties [66]. The brines of Sedum album (which is very rich in flavonol glycosides [67]) or the pickles of Portulaca oleracea (which have large amounts of ω-3 and ω-6 fatty acids [68] all represent really high gourmet challenges.

We must finally emphasize the importance of the Sauces group, since the most abundant list of species corresponds to those used as condiments. They are plants with essential oils, which are well-known in popular gastronomy and mostly belong to the Lamiaceae and Apiaceae families. In Table A1, these are assigned to number 21. However, we must emphasize them over the relevance of natural rennets such as Scolymus hispanicus, Cynara cardunculus, and Cynara humilis, because they open many possibilities of introducing new taste sensations and presentations. Something similar can be said about a potential flour use of Elymus repens or Scirpoides holoschoenus, [69] based in traditional knowledge about vegetal biodiversity. The latter is another food technology and scientific challenge, because the starchy rhizome is very rich in resveratrol and other antioxidant molecules that should be better studied for its best utilization.

5. Conclusions

The envisaged promotion of local products throughout environmentally sustainable techniques further contributes to environmental protection. The valorization of traditional foods and recipes is necessary in order to simultaneously preserve the local agro-biodiversity, sustainability, and productive systems. In this context, it is becoming important to address the consumer folk knowledge toward innovative applications. This strategy should represent a valid tool for the promotion of socioeconomic development, the enhancement of territories, and biodiversity preservation.