Canyon, Texas
February 1, 2008
Changing and growing markets have
renewed interest and research on guayule and lesquerella, two
native Big Bend plants that might be grown in other parts of
Texas, a Texas AgriLife
Research scientist said.
Dr. Mike Foster, a research scientist with the Texas AgriLife
Research and Extension Center at Lubbock, said he is looking at
the possibility of developing the two plants into alternative
crops in the Trans-Pecos and High Plains. Foster spoke at the
recent High Plains Vegetable Conference in Canyon.
The reason guayule is back on the forefront now is medical
products, Foster said. Many people are allergic to natural
rubber products, but guayule rubber does not seem to cause the
allergic reactions.
“There are about 300 medical devices that require natural
rubber,” he said. “Many occupations require people to wear
gloves and the guayule natural rubber does not produce the
allergic reactions because of fewer proteins. That’s where we
are headed with this.”
Guayule is a native shrub in the Big Bend area and produces
natural rubber, Foster said. This plant was harvested in the
early 1900s in Mexico and Texas and received attention in the
U.S. during World War II.
The Emergency Rubber Project was created in 1942-1944, and that
is when the first studies were performed on the reaction and
limitation of guayule to low-temperature environments in Texas
and New Mexico.
The experiments looked at 23 locations in the two states, Foster
said. Little injury was seen on dormant shrubs at temperatures
as low as 0 degrees, he said. Even in Dalhart, the plants had a
31 percent survival at minus 10 degrees.
Following the war, interest decreased and the U.S. became
primarily an importer of rubber that is derived from rubber
trees, Foster said. The rubber from guayule is structurally the
same. In the late 1970s, interest in domestic rubber production
was revived because of the oil embargo, he said. That’s when
researchers started trying to increase the biomass of these
plants. And now Foster is again looking at the plant with plots
at the Texas AgriLife Research Station at Halfway, near
Plainview. The Trans Pecos and Plainview areas have similar
elevations and temperatures, but the Plainview area receives
almost two times as much rain. The freeze dates are similar.
The plants were transplanted in May 25, 2006, and received a
total of 23 inches of water (rain and irrigation) during the
growing season. Foster said he has already determined the high
biomass lines that have been recently developed will not work in
the colder regions because they lost their cold tolerance during
the breeding process.
He has determined winter survival requires a dry period in the
fall followed by a gradual temperature decline. Problems can
arise if plant growth is induced by a winter warm period that is
followed by frost. However, two breeding lines are showing
potential.
The shrubs are harvested at two years of age when the whole
plant can be dug up or it can be clipped and left to regrow,
Foster said. It will need to be grown under irrigation, but the
water requirements for the High Plains have not been determined.
“One of the advantages here (in the High Plains) is you get some
rainfall, so it can reduce the water inputs,” he said. “The
Trans Pecos, where it is native, has trouble with salinity in
the water, so we’re just trying to see how adaptive it is in
this region.
“If this really happens, I think the High Plains would be in
position to cash in on the market,” Foster said. “One of the
last reports I saw, natural rubber varied from $1.30 to $1.60 a
pound. With the medical application, the demand is growing.”
Foster said the co-products may be as valuable as the rubber. To
process guayule for rubber, the plant has to be ground up and
the rubber comes from the bark. The resin can be used to treat
wood, and the leftover pulp can be used for composite boards and
as an energy source, i.e. fire logs, briquettes and fuel
pellets.
Lesquerella, the other crop Foster is working with, has
potential as an industrial oilseed crop, he said. It also is
found in Mexico and the Trans Pecos, but can be found growing as
far north as Kansas.
The cool season perennial produces oil similar to that of
castor, he said. All U.S. castor oil is imported.
The plant produces yellow flowers that develop into capsules
containing numerous small, flat seeds. One million seeds weigh
only 20 ounces, Foster said.
The seeds can be crushed to produce oil that could be used as
the base-stock to improve viscosity of 2-cycle engine oil, motor
oil and hydraulic fluid, he said. It also can be used in
biodegradable gear oil with off-shore drilling applications, and
it has potential as a biodiesel/biofuel additive.
“We certainly see this can be a potential new crop for the Trans
Pecos and High Plains regions,” Foster said.
He said he is working with a research group at Pecos and Halfway
research stations. The first planting at Halfway in 2006 had a
weed problem and they were not able to harvest. A second crop
was planted in 2007 and will be harvested this spring.
Foster said once the viability of the crops is determined, the
acceptance of them as an alternative crop will depend on the
ability to get them processed and to a market with a reasonable
profit.
by Kay Ledbetter |
|