Search for salt tolerant grasses aims to improve roadside plantings

July 02, 2008

KINGSTON, R.I. - July 2, 2008 - Standing in a greenhouse at the University of Rhode Island, Rebecca Brown was smiling even though it appeared that something had gone terribly wrong. Almost all of the 16 species of grass she planted last February in hundreds of small pots were dead.

The associate professor of turf science wasn't surprised. That's because the pots had been sitting in increasingly saltier water for five months, and few varieties of grass can put up with that environment.

Her aim, with funding from the Rhode Island Department of Transportation, was to identify a salt tolerance limit for native and ornamental turf grasses in hopes of finding a variety that can be used along highways without being killed when roadway salt - mixed with melting snow - is splashed onto the grass.

"The grasses we use in our lawns and along the roads in Rhode Island aren't adapted to salt, and they don't adapt over time because we don't allow them to go to seed," Brown said. "And salt tolerant western grasses may not grow well here because our salinity is only seasonal -- in the winter the grass has to survive the road salt, but during the rest of the year salt isn't a factor because our soil doesn't hold the salt."

So she used an ebb and flow hydroponics system to pump salt water into trays of grass to ensure consistent salt levels, starting with 2,500 parts per million of salt in February and increasing it by 2,500 parts per million every other week. In June, when the trials ended and most of the grass was dead, the salt concentration in the water was 22,000 parts per million, which is two-thirds the level of seawater.

Brown was pleased with the results. She pointed out a few tiny blades of green grass amidst the carnage, most from a variety of alkali grass that is known to be somewhat salt tolerant, as well as a couple samples of tufted hair grass and one red fescue.

"That one must have good genes," she said, "since none of the other fescues survived."

Her next step is to take the hardiest samples, plant them in the URI turf fields, collect their seeds, and through a process of selection develop a new variety of salt tolerant grass. Then she will test it again and evaluate how well it responds to mowing.

Brown said that the "salt zone" for Rhode Island highways is from 5 to 20 feet from the edge of the pavement, which is based on the distance that cars splash winter slush. It's for use in that zone that the Department of Transportation is seeking a better grass.

The department typically plants a mix of red fescue, perennial rye grass and Kentucky bluegrass along highways, but Brown said that rye and bluegrass grow poorly in roadside soils that are typically low in fertility. She also noted that most fescues are intolerant of salt.

While the research project is driven in part because the U.S Department of Transportation mandates the use of native grasses along roadways, Brown believes that the best alternative for Rhode Island will probably be an improved variety of red fescue - a plant which may have been introduced during colonial times - that she hopes to develop.

"It seems to do better than our native grasses," Brown said. "We should just use it because it works."

Or, more appropriately, because it lives.
-end-


University of Rhode Island

Related Salt Articles from Brightsurf:

A salt solution toward better bioelectronics
A water-stable dopant enhances and stabilizes the performance of electron-transporting organic electrochemical transistors.

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.

New technology helps reduce salt, keep flavor
A new processing technology out of Washington State University called microwave assisted thermal sterilization (MATS) could make it possible to reduce sodium while maintaining safety and tastiness.

The salt of the comet
Under the leadership of astrophysicist Kathrin Altwegg, Bernese researchers have found an explanation for why very little nitrogen could previously be accounted for in the nebulous covering of comets: the building block for life predominantly occurs in the form of ammonium salts, the occurrence of which could not previously be measured.

Salt helps proteins move on down the road
Rice chemists match models and experiments to see how salt modifies surface interactions in chromatography used to separate valuable drug proteins.

Mars once had salt lakes similar to Earth
Mars once had salt lakes that are similar to those on Earth and has gone through wet and dry periods, according to an international team of scientists that includes a Texas A&M University College of Geosciences researcher.

Marathoners, take your marks...and fluid and salt!
Legend states that after the Greek army defeated the invading Persian forces near the city of Marathon in 490 B.C.E., the courier Pheidippides ran to Athens to report the victory and then immediately dropped dead.

Water solutions without a grain of salt
Monash University researchers have developed technology that can deliver clean water to thousands of communities worldwide.

Solving the salt problem for seismic imaging
Automated imaging of underground salt bodies from seismic data could help streamline oil and gas exploration.

Higher salt intake can cause gastrointestinal bloating
A study led by researchers at the Johns Hopkins Bloomberg School of Public Health found that individuals reported more gastrointestinal bloating when they ate a diet high in salt.

Read More: Salt News and Salt Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.