"Wonder Leaf"

  Neem growing on the roadside near Port-à-Piment, Haiti

Neem growing on the roadside near Port-à-Piment, Haiti

As a tropical botanist, my research and training has taken me all over the tropics. This area of the world is generally characterized by its year-round warm climate and lush vegetation. The incredible species richness and biodiversity is what initially drew me to this area of research. The most common reaction upon walking into a tropical rainforest for the first time is likely to be “Wow! It’s so green”, but after awhile you start to notice other colors: blue Morpho butterflies, red Passiflora flowers, purple and orange fruits. During a recent fieldwork trip to Haiti I was reminded that even seasoned researchers can be awed by the sheer scope of biodiversity that exists within our tropical rainforests, or in this case lack thereof.

The island of Hispaniola sits in the Caribbean Sea south and east of Cuba, and is brusquely divided into the countries of Haiti and the Dominican Republic. As home to over 10 million people Haiti is currently the most populous country in the Caribbean. The large population has in part contributed to the severe deforestation Haiti has suffered; forests that once covered 60% of the Haitian side of the island now cover a mere 2%. To my trained eye, all I could think was “The forest! It’s all gone!” However, when I really started to look, I realized that many of the native plant species have been replaced with introduced invasive species. This is not typically uncommon in disturbed areas, and thus is not surprising for Haiti. Upon first glance, the roadside slopes look awfully green, but look again and you’ll notice that it’s all one shade of green: Neem.

A member of the Mahogany family (Meliaceae), the scientific name of this plant is Azadirachta indica, but it has been referred to as the “wonder leaf” and is commonly called ‘Neem’. Neem is a fast growing, drought resistent tree, and is considered a ‘weed’, taking advantage of its ability to conquer disturbed areas. Its weed status also means its sale and transfer are banned in certain countries. Though Neem has been used in ayurvedic medicine, taken internally as well as used topically, and eaten as a vegetable, its apparent impact on Haiti was staggering to me. Not native to Haiti or anywhere in the Caribbean, Neem is considered an exotic species, originally from India. Native species are plants that occur naturally or have been growing in an area for many years. A non-native plant species is sometimes called ‘exotic’. When a plant species is described as exotic, it means that it was introduced to an area either deliberately or accidentally, but usually by human activity. When an exotic species is invasive, it is likely to cause economic or environmental harm. In the case of Neem, from a critical botanical standpoint, I see it as an invasive species, as it grows in spaces where native plants could and should be growing. Native species often include endemic species, or species that occur only in that area and grow nowhere else and they are often equipped to grow and thrive in a particular area. Native species usually have an important role in the local ecosystem, for example native trees provide food and shelter for native wildlife where an introduced species may not. From a botanical standpoint and as someone who cares deeply about conserving worldwide plant diversity, monocrops, such as what I saw with Neem, are never a pretty sight.

When I started looking into Neem a little bit more, I had to take into consideration the complexity of Haiti, with its extreme deforestation and poverty. I realized that it isn’t so off the wall that Neem would be planted for reforestation efforts. USAID planted more than 200,000 Neem trees in a ‘road beautification’ project. The trees grew so well that the seed is now a Haitian export. Neem plants are generally planted in areas desperate for fuelwood, of which Haiti is. Only one quarter of the population has access to unstable electricity (prior to the 2010 earthquake), which leaves everyone else dependent on charcoal and diesel generators. In areas deemed ‘hopeless’, any planting is usually considered a step in the right direction. Especially in the Caribbean, an area plagued with annual hurricanes and tropical storms, plants act as a windbreak and help during flooding by reducing erosion and siltation.

Moral of the story? Neem probably isn’t the worst thing to see growing everywhere in Haiti. However, there are many native species that would be more beneficial to plant in future road beautification and reforestation projects. 

 

https://www.nap.edu/read/1924/chapter/10
https://www.usaid.gov/haiti/energy