Inga edulis
The ice-cream bean tree, also known as joaquiniquil, cuaniquil, guama, guaba, or its Latin name, Inga edulis, originated in South America. Indigenous peoples of the Amazon cultivated it for timber, shade, medicine, and of course its beans (the pulp of which, as its colloquial English name suggests, tastes reminiscent of vanilla ice cream).
A leguminous tree, it can form symbiotic relationships with rhizobial bacteria and mychorriza to fix nitrogen in the soil. It also forms symbiotic relationships with ants to protect it from herbivores.
#Human relations
As climate change heated up more of the globe during and immediately after the collapse of civilization, humans spread the ice-cream bean far beyond its native tropical bioregions. Its rapid growth, nitrogen-fixing properties, and resilience in the face of both flooding and drought made it a popular choice for restoring depleted soils.
In particular, it became the basis for a method of horticulture known as Inga alley cropping, an alternative to swidden cultivation. In this system, the ice-cream bean trees are planted close together in rows, with an "alley" of about four meters between each row. After two years, the trees have grown and filled in the canopy. The gardeners then prune the trees, using the larger branches for firewood and leaving the smaller branches and leaves on the ground as mulch. In the mulch, the gardeners plant other crops (for instance, the Three Sisters). Gardeners continue to prune the ice-cream bean trees, adding more mulch to protect the crops below and add a new top layer of soil over time.
#Ice-Cream Bean People
When a community focuses on its relationship with the three sisters to make a living, it can shape their lives in a wide variety of ways. A few examples include: