By David Ostdiek
Crops growing in the numerous small plots at the university's Panhandle Research and Extension Center this summer will include the usual assortment of dry beans, corn, sugar beets, peas, and various alternative crops. In their midst, one small plot has rows of plants that look like the dandelions in local yards.
In fact, they are dandelions of a different type. Their roots produce rubber, and this test plot is part of a multi-state collaborative project to see if rubber and biofuels can be grown and processed in the United States from dandelions. The project is titled Biofuel and Rubber Research and their Agricultural Linkages (BARRAL).
Figure 1. Nevin Lawrence, integrated weed management specialist, shows an individual rubber dandelion plant in the greenhouse at the University of Nebraska-Lincoln's Panhandle Research and Extension Center.
According to the project proposal, this effort aims to develop rubber dandelion (or TK for the plant’s scientific name, Taraxacum kok-saghyz) as an alternative to help meet the country’s critical need for both transportation biofuels and a domestic supply of natural rubber. It is believed that rubber dandelion could meet both these needs.
Inulin and biomass from the plant can be converted to biofuel, and the natural rubber produced from the plant has qualities almost identical to the rubber extracted from rubber trees, and can be similarly used for a variety of applications, including technically sophisticated, high performance automotive tires.
The BARRAL Consortium is led by The Ohio State University, and has a goal of overcoming potential barriers to commercialization of rubber dandelion. Some of these barriers include
- mechanical operations, such as planting and harvesting;
- the agronomy practices used to grow the crop in certain regions;
- handling, storage, and bioprocessing of rubber and biofuel from the dandelions; and
- the larger impacts that a rubber-producing industry might have on the northern United States.
The three-year project is funded by a grant for $2 million, funded jointly by the Department of Energy and U.S. Department of Agriculture. It has several components, including plant breeding, processing (turning the dandelion roots into rubber), and agronomics. At the Panhandle Center in Scottsbluff, the focus is on the agronomic element, and it is led locally by Nevin Lawrence, integrated weed management specialist.
Figure 2. Lawrence checks a tray of rubber dandelion plants started in a greenhouse
One-fourth of the $2 million total funding goes to the University of Nebraska. The grant will pay for labor, equipment, and materials.
Two other specialists from the Panhandle Center will also be involved. Bijesh Maharjan, soil and nutrient management specialist, and Xin Qiao, irrigation and water management specialist,will co-coordinate the irrigation and fertility study.
The research in Scottsbluff will focus on
- what equipment and methods can be used to establish a crop;
- the optimal length of growing season;
- the irrigation and fertilizer requirements;
- how to improve weed control; and
- the optimal harvest methods.
So far, the dandelion plants are proving difficult to get started in this region’s light soils and windy spring conditions, Lawrence said. Several dandelion plots have been seeded at the Panhandle Center to compare various soil treatments. Some rows are covered with manure, some with straw, and some with char, a coal combustion residue created as a by-product of refining sugarbeets at regional sugar plants.
Rubber dandelion could be a new source of natural rubber in the event of a sudden global shortage. Currently, all commercially available natural rubber is produced from rubber trees in tropical countries, more than 90% in southeast Asia.
The United States imports 1.5 million tons of natural rubber per year for manufacturing, as well as for vast quantities of finished goods. Currently, there is a global shortfall in natural rubber production; as other countries develop, so will global demand.
This puts the United States and other importing countries at risk of high prices or unavailability of natural rubber.
According to Lawrence, the project got its start with a biochemist from The Ohio State University, Katrina Cornish, who made a presentation at a biochemistry conference. Cornish was studying the dandelions, but found that they would not grow well in the heavier soils typical of Ohio, Lawrence said, but that a lighter, sandier soil might work. Cornish is the Endowed Chair and Ohio Research Scholar, Bioemergent Materials, in the Department of Horticulture and Crop Science and Department of Food, Agricultural and Biological Engineering.
Figure 3. Rubber dandelion plants in a plot at the Panhandle Center. The soil treatments include manure, straw, and char.
The suggestion that the Nebraska Panhandle might have suitable soils came from Donald Weeks, an emeritus professor of biochemistry at UNL. Weeks contacted Jack Whittier, director of the Panhandle REC, who agreed to pursue the project with Lawrence as the lead for the agronomics section.
In addition to the Nebraska Panhandle, agronomic research is being conducted at Oregon State University and The Ohio State University, Lawrence said.
To date, rubber from dandelions has not been commercially grown and processed, but Ohio State has contracted with an Ohio grower to produce a small amount that has been processed on a small scale. It was used to manufacture tires and other products that match the quality of existing rubber, Lawrence said.
Lawrence cautions that the dandelions will not become a major alternative crop for Panhandle farmers anytime soon. In addition to the agronomic hurdles of how to grow the crop in this area, there are questions about whether it will be possible to grow and produce rubber on a large scale that matches the quality of existing rubber products.