How ‘Intelligent’ Are Trees?

 

When it rains every day for months, the trees start closing in around our house in Fish Bay. We left most of the native trees on the property, and planted Arica palms and bougainvillea in the yard. When they all get bushy they block the path and the view. Definitely time to sharpen up the machete and get out the clippers.

Sometimes I feel a little badly about chopping back the native trees, but most of them don’t seem to mind a trim. The invasive trees I wish would disappear, like the false tamarinds, often grow back even more aggressively no matter how much I cut them.   

 I mentioned my tree-trimming work to a friend in the city, and she recommended that I read a recent article in the New Yorker magazine on ‘The Intelligent Plant’ by Michael Pollan. www.newyorker.com/reporting/2013/12/23/131223fa_fact_pollan. Back in 1973 a book called The Secret Life of Plants had suggested that plants could feel stress when people even thought about harming them. I wondered if she viewed me as a tree mugger.   

In the article, Pollan reported that the claims about plants having feelings have not been substantiated. However some scientists have documented plant behaviors that “look very much like learning, memory, decision-making and intelligence” as plants respond to a wide variety of information about their environment – including available levels of light, water, and nutrients, as well as temperature and soil conditions.

Even in the 1880s, Darwin’s research led him to believe that there was a type of intelligence in the root tips of plants that allowed them to process sensory information and in that way adapt to their environment.

More recent studies have shown that plants also communicate through chemical and electrical signals, and even share and information through widespread underground webs of fungi. Although most scientists do not conclude from this information that trees are ‘conscious’, it does seem that they may actually be ‘intelligent’ even though they do not have brains.

In fact, the lack of a brain may make plants more resilient to the impacts of environmental changes and destructive events.  They can lose up to 90 percent of their mass and still survive and grow back.  (Plus they can make their own food from sunlight and water.) 

Rather than viewing plants as insensate, lower life forms, Pollan suggests that their way of adapting to the world could provide a model for our own future, one that is “organized around systems and technologies that are networked, decentralized, modular…and green, able to nourish themselves on light”.

It’s interesting to think about what we could learn from the trees about survival skills – especially the trees that are well-adapted to island life. In the short term I am still planning to cut back the trees in my way, knowing they can manage okay with a few less branches. I’m sure some of them will still be going strong long after I am gone.      

Pig Turds, Gri-Gris and Water Mampoos

 

 

Generally, if you show people a picture of a landscape they don’t think ‘Oh look at all the interesting types of trees.’ They will focus on the other things in the picture – the flower, the deer, or the couple on a blanket – with the greenery mostly just a backdrop for the real action.  

So, for years I drove around in St. John and didn’t pay much attention to the trees unless they had fruit on them, or the ‘bush’ got so thick it encroached on the road. But now I have finally gotten acquainted with some of the more noticeable local trees. I give them a nod as I pass by, and the road seems less lonely.

I was inspired by a book Remarkable Big Trees in the US Virgin Islands. I had just identified a few of the native trees on my own land, and thought it would be interesting to see what remarkable big trees I could find in my Fish Bay neighborhood. Much of the area nearby is owned by the Island Resources Foundation as conservation land, so that seemed like a good place to start.

We took digital photos of some of the larger trees, and GPS coordinates so we could map them, or find them again later. We sent the photos to Eleanor Gibney, a local plant expert and author of a book about native trees, who helped us identify some of the trees. To me, many of the trees and leaves looked very similar. It’s like learning a new language, reading the tree leaves to figure out their identities. It helps a lot to distinguish them if the trees are in bloom, or have fruits on them.

 
Our top ten list of trees in the Fish Bay flat land included: black and red mangroves, genips, gri-gris, hog plums, mahoes, pig turds, sandbox or monkey-no-climb trees, tamarinds and water mampoos. 

Big trees have long had cultural significance as boundary markers, landmarks, shady areas for open markets and spaces for cultural and political assemblies. Eleanor Gibney told us that during the 20^th century the large old trees in Fish Bay probably provided shade for cattle, while the rest of the land was cleared for grazing. In the colonial era there were cotton plantations in the area and much of the flat land was cleared of smaller native trees at that time, but until recently the hillsides around Fish Bay were some of the least disturbed on St. John, with an abundance of rare and threatened species.

Several of the trees we found – tamarind, gri-gri, water mampoo, sandbox and genip – were highlighted by Robert Nicholls in the Remarkable Big Trees book as ‘spirit trees’. These trees were traditionally viewed as mediators between human society and spiritual and ancestral realms, in addition to being providers of food, fuel, wood products and medicines. The book explains that beliefs about spirits in trees were transplanted from Africa and attached to similar tree species found in the Caribbean. Some trees were believed to be inhabited by ‘jumbies’ – a term usually thought of as meaning ‘ghosts’, but also referring to animistic spirits that occupy natural objects.

Large boles, buttress roots and caves formed by protruding roots are all indications that jumbies are living in a tree. I have to say I did notice that some trees really look like they have strong personalities, and I try to always be very respectful of them.  

On the eastern side of the flat land, past the one-way bridge, there is a long stretch of road skirting the edge of a wetland area that is mostly covered with black mangroves. The land here is salty and appears to have been flooded at times by water coming in from the bay. Closer to the shoreline there are red mangroves whose above-ground roots seem to walk out into the bay. Egrets and herons roost in the mangroves, along with pelicans and other indigenous and migratory birds. The shallow water around their roots serves as a nursery for many types of fish – and watch out for the baby sharks! The mangrove roots also filter storm water and collect silt, which helps prevent erosion, and runoff of sediments and pollution into the bay during periods of heavy rain.

 

For more information see the report

TREES IN THE FISH BAY FLAT LAND - Island Resources Foundation

www.irf.org/mission/protection/IRF%20TREES%20report.pdf w shared post