THE ROLE OF SCHOOL GARDENS AS CONSERVATION NETWORKS FOR TREE GENETIC RESOURCES
Trees play an important role in children’s development and learning. We all remember climbing trees as children as well as the excitement that this brought and the trees’ important role in our outside play. Trees are critical to human health and well-being in multiple ways, supporting biodiversity; providing important food and medicine; and helping to ensure climate amelioration, both locally and globally. Trees can be living climbing frames but also living laboratories for learning. It is estimated that we have about 3 trillion trees on the planet, which amounts to about 400 trees per person of the global population; this is about 50% of the trees present prior to human population expansion and industrialization (Crowther et al., 2015). Indeed, increasing human pressure on planetary ecosystems is leading to a massive depletion of forest cover and biodiversity as well as declining human health. Large-scale agriculture focussing on only a few crops is leading to environmental degradation and habitat fragmentation as the most significant driver of biodiversity loss (IPBES, 2019). This is having a devastating impact on global tree species, with 10,000 species1 threatened with extinction. We currently have around 60,000 species of tree on our planet, but less than half of these have any documented conservation status2 (see Botanic Gardens Conservation International).
School gardens or environs can play a key role in counterbalancing some of these challenges, acting as repositories for biological diversity. They provide a place where native tree species can be safeguarded and cultivated, and traditional knowledge about the different uses of trees can be shared (Cousins and Witkowski, 2015). For example, the recent Lancet report on food in the Anthro- pocene and the role of healthy diets from sustainable food systems shows that increasing our consumption of fruit and nuts (the majority of which are produced from trees) will be critical to ensuring more sustainable global diets for both humans and the planet (Willet et al., 2019). Trees planted and preserved in school gardens or environs can have additional functions, providing shade and improving local climate but also providing green spaces vital to mental well-being.
The aim of this chapter is to explore the potential of school gardens as a multidisciplinary tool used to address continued threats to tree biodiversity. We discuss how school gardens can increase students’ familiarity with tree conservation issues, identification, and sustainable use when used in curricula. In addition to supporting and providing evidence of the benefits of the conservation and restoration of traditional and threatened tree species, school gardens can be a way to support the recommendations of international agencies, which are increasingly including the role of underutilized species in food policies to fight hunger and malnutrition, and in environmental policies to enhance biodiversity.
Linking appreciation of trees to better diets, livelihoods, and learning
Collecting fruit and nuts from edible trees is commonplace to some children, but in more urban environments, the planting of edible fruit or nut species is not common. Enhancing the planting of native fruit and nut trees within school gardens, as well as encouraging children to bring seeds and fruits of native trees to school as part of class activities, can raise awareness of their value. This also offers learning opportunities for botany, ecology, and biology. Children can discuss what might disperse the seeds in nature, germinate seeds at school, and record the seeds’ growth and development.
School gardens that include indigenous fruit trees can be a source of extra income for schools as well as a place to conserve, register, and study genetic diversity. Linking indigenous vegetables and fruit to markets can be an incentive towards their inclusion in school gardens. A recent study shows a shift in production trends towards traditional products in Tanzania (70% increase) and Kenya between 2002 and 2006, once producers were linked to informal and formal markets (Ojiewo et al., 2013). Additionally, in the Chivi district of Zimbabwe, a participatory planting test was conducted on indigenous trees, such as Afzelia quanzensis, not only for timber but also for carving sculptures and utensils (Gerhardt and Nemarundwe, 2006). Depending on regrowth rate and the timing of trees, manual activities like these can be listed as one of the advantages of having indigenous trees besides for food or shade. Indigenous fruit trees are also considered providers of regular and low-risk returns (Schreckenberg et al., 2006), another reason to include them in school gardens.
Another example of regional tree domestication with an important socioeconomic role is the marula (Sclerocarya birred subsp. caffra) in Southern Africa, which is used by local communities for many purposes: kernels are eaten or used to extract oil, fruits are eaten fresh or fermented for alcoholic beverages, leaves are to feed livestock, and so on (Shackleton, 2002). More specifically to school gardens, in the Ugandan Slow Food school garden in Kiboobi Village, Lwengo district, blackjack (Bidenspilosa) is used to treat cuts and help stop blood flow, while stinging nettle (Urtica massaica) is used for urinary problems. Cultivation of local cultural trees increases the diversity and complexity of the territory (Lin et al., 2015), with multiple health benefits. In sub-Saharan Africa, growing domesticated and wild local fruit tree species is one smallholder strategy used to increase economic revenue and health and ecosystem services, as in the case of tree species such as guava (Psidium guajava), baobab (Adansonia digitatd), and moringa (Moringa oleifera). By increasing the number of indigenous fruits and vegetables in school gardens that are made accessible to the community, students can reduce exploitation pressure on the natural habitat, helping to support in situ conservation of native trees. Researchers found that students exposed to school gardens can educate their parents and siblings about what they have learned, thereby influencing the eating habits of their whole household (Heim et al., 2009) and changing eating preconceptions, as in a case study in Kenya (Kehlenbeck et al., 2013) which showed that adults see fruits as food mainly for children and consume only those with a perceived higher energetic value, such as tamarind or baobab fruits.
BOX 7.1: MORINGA TREES TO IMPROVE DIETS AND ENVIRONMENTAL AWARENESS IN BRAZIL
Despite the country's rapid economic growth, people in Brazil continue to suffer from hunger and malnutrition, and rural areas are consistently worse off than urban areas. In 2010, field staff of Trees for the Future (TREES) noted that schoolchildren were eating their main meals at school because there was not enough food at home. Furthermore, local markets lacked the necessary options to provide children with a diverse diet. TREES identified moringa (Moringa oleifera) as a species with the potential to overcome some of these challenges and began integrating it into school curriculum and meals. Moringa is often referred to as the magical tree because of its rapid growth and resistance to drought and poor soils, and its nutritional leaves, rich in antioxidants, vitamin A, and vitamin C.
TREES introduced moringa trees into two schools in Marilia, Brazil, through a three-step programme. First, teachers created a curriculum that included topics such as recycling, sustainability, and food security to help students understand their relationships with the environment, and help them develop 'an environmental conscience'. Second, students brought empty food packages to recycle into plant pots. TREES staff provided moringa seeds and supervised the students as they planted the seeds. The school designated a nursery area for the seedlings, which were pruned of leaves about once a month. As a third step, at the end of the school year, children took their moringa saplings home to plant in their home gardens and thereby also
(Continued) leave the nursery empty and ready for the following year's students. During this last step, parents were invited to participate in TREES workshops at the schools, during which they were taught how to grow a variety of plants in a small space and how to use moringa in their cooking. After the saplings had been planted in the home gardens, TREES staff visited the families to measure the trees and give additional advice. Parents were encouraged to report back on how they put moringa to use in their kitchens and how the trees were benefitting their families.
The project showed positive results: environmental awareness increased both for children and for their parents in terms of more considerations of good environmental practices, such as recycling. An increased nutritional awareness was also detected, with 90% of the families experimenting with moringa recipes at home and 55% eating homemade moringa powder three times per week. The project even showed some positive impact on education, with overall better attendance and higher grades. Students who had problems in class often became responsible for nursing the moringa trees, which gave them a valued role in class and increased their self-esteem.
Read more about the project: www.b4fn.org/case-studies/case-studies/ moringa-leaves/