-E. Taylor
You may have a potential biofuel source emerging in your field right now and not even know it. According to an article on AgriNews Online (”Producers growing weeds for fuel“) some growers in Illinois are planning on growing field pennycress for biodiesel production. Field pennycress in a winter annual weed, meaning it emerges in the fall and reaches maturity sometime in the spring/early summer, so in Illinois they are thinking about planting the pennycress into corn stubble in September/October and harvesting in early June, hoping to still get in a soybean crop. Pennycress is a member of the mustard family, it begins its life as a rosette and produces flowers and seeds on a bolt. Though pennycress can be confused with other weeds, such as shepherd’s purse, it can be distinguished by the sulfur smell it emits when the leaves are crushed and the rounded capsules which hold the seeds. In the article, they report that the oil content is nearly twice that of soybean. I have studied the lifecycle of field pennycress for the past few years so I had a few thoughts.
- From what I have seen in naturally emerging pennycress plants in Michigan the plants begin to drop mature seed somewhere between the 1st to 3rd week in June. When the dispersal first begins not all of the seeds on the plant are mature, they mature from the bottom up. For us, harvesting pennycress this late in the planting season would potentially be too late for a soybean crop.
- I have found pennycress seeds to be very easy to harvest by hand for use in laboratory and greenhouse experiments, especially compared to other winter annuals such as common chickweed and henbit. The seeds seperate easily from the capsules. Because the seeds sit high above the rosette of the plant I would imagine that with the right setup they would be fairly easy to combine.
- One greenhouse study, published in Weed Technology by Venkatesh et al. in 2000, showed that field pennycress is a potential alternate host for soybean cyst nematode, so this may be an important consideration in some areas.
Who knows where this weed will end up in the grand scheme of biofuels, but it is kind of fun for weed nerds like me to think about. As a side-note, I will be presenting a poster on pennycress entitled “Temporal seed rain and dormancy of field pennycress and common chickweed” at the upcoming NCWSS meeting in Kansas City, MO.
Thanks to Joe Armstrong for sending me the article.
