The scariest thing about the jungles of the Samoan islands that I saw was how they were disappearing at an alarming rate...and not just because of humans for a change.
Taking over everything that I saw in a lot of places was a broad leaf vine known as fue saina if you were Samoan, Mikania micrantha if you were a scientist, and 'Mile-a-minute weed' if you were trying to get rid of it. The plant was a native of South America and has been spreading around the planet since about WWII.
I didn't know you could get an award for being a vine. This species was nominated
as being among the "World's Worst" 100 invaders by the Invasive
Species Specialist Group of the World Conservation Union Species Survival
Commission. I wonder what the statue looks like? I hope it wins.
The vine does its job by covering everything and blocking out the light. The plants under it just can't get enough light and they die. Since it is a vine it can also crawl up into a tree, take over all of its branches, and block the light from reaching the leaves. As if that weren't efficient enough, there is some evidence that it also chemically prevents the other plants in the area from growing.
Use as cattle feed, a cover crop, and as a garden plant (it has a flower) has helped it to spread. One plant can cover an area about 15 feet by 15 feet in a few months and produce up to 40,000 seeds per year.
In areas of the forest, in the picture below, where this vine was not covering everything the ground was covered with ferns. In areas where the vine had taken hold, like in the picture, the ferns didn't stand a chance, and soon, neither would anything else.
So it was back to Apia for a day or two -- I got "stuck" there because of the lack of airplane seats -- and then back to Pago Pago. One country's worth of the adventure was over.
2014-07-24