October 15, 2013
Named after a German artist, Ludwig Choris, the Floss silk tree, Chorisia speciosa, is called ‘Palo barracho rosada’ (‘rosy drunken stick’) in its native Argentina because of its odd-angled branches and pink flowers. In the fall it produces a spectacular show of orchid-like pink blooms and then a large crop of avocado like green pods that eventually explode in the spring to produce cotton-like masses of seed impregnated fibers. Here at the Arboretum parrots swarm to the newly exploded fruit to consume the seeds and in the process cause the fibers to scatter in the warm spring breeze like snow. This fiber is resistant to insects and rotting and has been used for pillow stuffing and, because it floats, has been used in life vests and preservers as well. Probably the most interesting use of this fiber has been to acoustically deaden recording studios and radio broadcast rooms. Besides using its fiber Argentineans and Brazilians have used the wood for canoes (it’s almost as light as balsa) and the tree is planted extensively in its native range as an ornamental.
In its native, mostly frost-free range Chorisia endures dry seasons and droughts by losing its leaves; however unlike trees in temperate regions where a thick layer of bark is needed to insulate the sensitive layer of food and water transporting tissue known as the vascular cambium from the freezing cold, Chorisia’s trunk has a very thin layer of protective tissue. This thin layer allows light to pass through photosynthetic cells containing chlorophyll. This is why Chorisia’s trunk appears green. Because the trunk has no bark to protect it from animals that might eat it, large spines cover it and the larger branches of the tree -this is why you’ll rarely see a Chorisi