Lettuce Rubber, and a Crack in the Carbon Sink

We know that the vegetables we eat today are intensely modified versions of once wild plants, right? Selective breeding and whatnot.  Some of those ancestral species are still around, but we don't really eat them.

Take prickly lettuce, great great great grandmother to the salad greens tucked into by the boatload daily. Also a type of milkweed. Classified now as an official big pain in the ass, it's the bane of many farmers existence. It's drought resistant, grows rather tall, a damn good grower. And thanks to a bit of scientific ingenuity, it may be a new cash crop. 

Researchers at Washington State University have been looking at prickly lettuce as new temperate climate source for rubber, perhaps replacing, or at least reducing, dependence on trees or petrochemical sources. 

The benefits, according to a release: 

Natural rubber is the main ingredient for many everyday products, from boots to condoms to surgical gloves. Roughly 70 percent of the global supply of rubber is used in tires.

But more than half of rubber products are made from synthetic rubber derived from petrochemical sources. And the largest source of natural rubber, the Brazilian rubber tree, is threatened by disease.

When lettuce bolts, it produces a white sap that shares genetic traits with natural rubber. With a little selective breeding for water efficiency and early bolting could mean prickly becomes an integral, and profitable, rotation crop. It also means jimmy hats made out of lettuce sap. Just sayin'.  

Crack in the Carbon Sink

In worse, bad, horrible news: Soil, which has been considered a carbon sink, meaning it absorbs more carbon than it releases, isn't doing exactly what we thought it was: trapping carbon for millennia. Plants, soil and oceans are all examples of carbon sinks. Some have used the idea of carbon sinks to promote continued fossil fuel use, but such thinking simplifies the intricate interchange between different carbons and sinks. Plants fix carbon in their roots during photosynthesis, then shifting the carbon into the soil via chemical/microorganism interaction. And there it stayed, for many, many years. Or so we thought. 

New research shows that a root chemical, oxalic acid, breaks down carbon bonded to minerals in the soil, therefore releasing carbon back into the atmosphere. This new study, by scientists at Oregon State University, disputes prevailing thinking on the soil-carbon relationship, but explains the full carbon cycle. If they're right, soil carbon loss estimates could be off by at one percent, researchers think, which sounds small, but over time is gigantic. 

At this point, what we can say about the research is that soil, and carbon sinks in general, are not saviors, and we need to keep looking at fossil fuel reductions.