Thursday, July 29, 2010

Close-up Pictures of the Suspected Herbicide Carryover Damage on Tomatoes

Please read the previous post to find out the details here. In short, these are pictures of tomatoes that have been growing for five weeks in standard potting media, potting media with hay suspected of having herbicide on it, and composted manure suspected of having herbicide residue. We saw no damage at three weeks (see earlier post). Here are close-up pictures of the damage.

These first six are of plants grown with suspect composted manure:

The picture below is of a plant grown with suspect hay. Note that leaves are just starting to curl.

The picture below of a plant grown in standard potting mix.

Wednesday, July 28, 2010

Late Blight Confirmed (Really) in Henderson County, NC

Variety trial from 2009 showing late blight resistant (background)
 and late blight susceptible (foreground) tomato varieties

I am just going to copy our pathologist's email from 12:55 pm today.  Please keep in mind that this is aimed at western North Carolina.  If you live in another state or a differernt part of North Carolina, please contact your closest extension agent or state pathologist.

"Hey Everybody-

This morning we found and confirmed late blight (by microscopic examination) in one small shaded area of a conventional tomato field in Henderson County. We have not been able to confirm its presence anywhere else in the tomato production areas of NC this summer, so I believe this is the start of the tomato late blight epidemic in WNC. We've had some rains recently and I'm sure it's out there elsewhere now, or soon to arrive.

Fungicide recommendations for controlling late blight on fresh market tomatoes start at week 9 in the NC tomato foliar fungicide guide.  It can be found at this link.

In addition, there is information (fact sheet) on this disease in North Carolina, including pictures of the symptoms at this link.

Check out the different diseases and select the one under Tomato Late Blight.

Please make sure to get your preventative sprays on as soon as possible if you grow tomatoes in late blight prone areas. Chlorothalonil works well as a protectant if you do not yet have the pathogen in your field. If already established in your tomato field, it would be best to apply something more than a protectant like Presidio (+ chlorothalonil) or Ranman.

If you need a confirmation of late blight in your fields, please do not hesitate to call your agent or my lab to submit a sample.


(Kelly Ivors is an Associate Professor and Extension Specialist in the Department of Plant Pathology at NC State University.  She is located in the same building I am in Mills River, NC.)

Organic Farmers:
If you are an organic farmer, click on "late blight" on the right side bar labels of this blog for more information on how to attempt to control this disease.  This is a very difficult disease to control with the organic options currently available.  Your best line of defense is to plant varieties with some late blight resistance.

Monday, July 26, 2010

Five Weeks After Planting Tomatoes in Manure Compost-Damage Evident

Some home gardeners in Asheville suspected plant damage from some composted manure they had purchased.  They wondered if it could be from herbicide carryover on hay that the animals who produced the manure had eaten.  The producer of the compost was puzzled because she was very careful when she purchased hay, asking whether herbicides were used, and she had performed her own bioassays and everything seemed fine.  The homegardeners were adamant, however, that the only plants showing the damage were the ones growing in the compost.  So, the compost provider brought us large samples of the manure and hay.  We took tiny tomato plants and planted them in the manure and with the hay.  You can see pictures of those plants at time of planting and three weeks later at:

Someone left a comment on that blog post saying we should grow the plants longer.  They didn't see damage on their own plants until much later.  One of the home gardeners I was doing this study for said the same thing.  He said to wait five weeks.  So we waited.

Five weeks have passed. This morning, my technician, Amy Hamilton, checked on the plants and took these pictures.  As you can clearly see, the plants growing with the composted manure are now exhibiting unusual growth.  I asked the pathology technician in our building, who has examined thousands of tomato plants in her career, to take a look at them and without hesitation she said "herbicide damage".  I will have our pathologist and weed scientist also take a look at these plants because I am not qualified to make a definite diagnosis myself.  But clearly, something is not right with these plants.

I am puzzled about why it took this long for damage to develop.  We planted very tiny transplants into the mix of composted manure and potting media and they grew fine for a long time.  But this also brings into question, at least to me, the bioassay procedures that we and others have in our publications on this topic.  We don't tell people to grow their test plants that long!  I will keep you posted as we learn more.

Tomatoes grown for five weeks in standard potting mix

Tomatoes grown for five weeks in potting mix with hay on top (it says straw, but it is hay)

Tomatoes grown for five weeks in manure compost and potting mix

Tomatoes grown for five weeks in manure compost and potting mix

Friday, July 9, 2010

Three Week Results of Bioassays Performed on Manure Suspected of Damaging Local Gardens


Damaged tomato plant in Asheville garden
Undamaged pepper plant in Asheville garden
Damaged pepper plant (where manure was used) in Asheville garden

In early June, some home gardeners in a neighborhood in Asheville had peppers and tomatoes that were very twisted and odd looking.  It looked very much like herbicide damage.  They asked around their neighborhood and no one reported using any herbicides, such as 2,4-D, so they tried to figure out what they had in common.  The common factor appeared to be manure they purchased from a local farmer.  The previous summer, a local organic farmer suspected he had plant damage from manure obtained from the same farm.  This was in the midst of all the reports of herbicide carryover (mostly aminopyralid and chlorypralid) in manure and compost.  However, when the farmer who supplied the manure grew plants directly in the manure pile (in 2009) they grew fine!  The manure provider, not wanting to cause damage to anyone's plants, made special efforts throughout the year to ensure herbicide-free manure in 2010.  In particular, all hay sources were questioned about herbicide use and bean bioassays were performed on the manure.  So, this farmer was frustrated and discouraged when the manure was again suspected of causing damage this year.

This is where I stepped in.  I asked that farmer to bring me some of the same manure that was being sold and some of the hay that was fed to the animals.  We set up our own bioassays, using small tomato transplants.  Tomatoes seem to be even more sensitive to the herbicides than bean and peas.  We grew plants in our standard potting mix (STD), in a 50:50 mix of manure and potting mix (COMP), in potting mix with hay on top (STRW) and we planned to use a manure tea, too, but we never did apply it.  So the (TEA) treatment in the photos is really just another control with standard potting mix.  Below are pictures of the results after three weeks of growth.

Planting Day
Top is with suspected hay and bottom with suspected manure

Both rows are in standard potting mix (controls)

Three Weeks Later
Grown with the suspected hay

Grown with suspected manure

The control, grown in standard potting mix

The manure and hay provided to us did not damage these plants after three weeks.  I assume the samples provided to us are representative of what the gardeners used. 


So, if this is the same manure the gardeners used, we still do not know what has damaged the plants in the gardens!  Although some diseases and insect damage can cause distortion, the damage these gardeners experienced really does look like herbicide damage.  But where the herbicide came from is still a mystery.  We do not know if it was air-borne drift or if it is in the soil.  Some of the gardeners were going to do some of their own testing, but I don't have those results back yet. I'll keep you posted!


Downy Mildew on Cucurbits Reported in Western NC

Yesterday I did a blog post on several diseases and insects to be on the alert for. This morning I found a post from extension agent, Sue Colucci, that downy mildew on cucurbits is now here in western North Carolina.  She has done excellent posts on downy mildew of cucurbits and basil (different organisms) on her blog.  I suggest you read those and become familiar with these potentially devastating diseases:

Thursday, July 8, 2010

Funds Distributed to Local Forest Products Businesses in Western NC

Natural ramps patch in western NC
Press Release: July 8, 2010


Second Phase of Awards to Boost Forest Products Industry

Asheville, NC – Land-of-Sky Regional Council (LOSRC) Chair Letta Jean Taylor today announced grants totaling $956,164 to 11 local businesses to produce jobs and stimulate the economy of Western North Carolina (WNC). The American Reinvestment and Recovery Act (ARRA) funds are the second round of economic stimulus awards provided by the USDA Forest Service’s Southern Research Station and dispersed from LOSRC to generate jobs by helping forest producers improve their forest products marketing and production methods. Total awards from both rounds come to $1,209,764.

“This has been a win-win partnership with Land-of-Sky and Western North Carolina communities. Combined with the first three projects unveiled on June 2, Land-of-Sky has now distributed stimulus funds to help 14 businesses across the region, which has created an estimated 141 jobs of under-or unemployed forest producers,” said USDA Forest Service Southern Research Station Director Jim Reaves. “I believe these projects will help jumpstart the forest products industry and the economy of Western North Carolina.”

“We have some of the most productive forests in the country and it is important that we use that asset wisely to support the economies of our rural communities,” said Taylor. “These stimulus projects give us an opportunity to use our renewable forest resources to bring back many of the jobs lost in the economic downturn.”

The businesses selected for funding through the Western North Carolina Forest Products Cooperative Marketing Project include a diverse group of forest enterprises. The companies will use the funds to expand and diversify their businesses. LOSRC awarded more than $250,000 to Appalachian Designs, Bark House Supply Company, and the Boggs Collective during the first award phase. This second phase provides awards to the following businesses:

Clear Creek Wood Products is receiving $81,500 to operate a shaving mill from small diameter timber procured from area harvesters.

Community Forestry Project will use $99,998 to promote sustainable forestry through worker training, product development and cooperative marketing in horse logging, sawmill operation, and production of value-added forest products.

Green River Forest Products is receiving $88,050 to construct dry kilns to bundle, market, and transport environmentally safe and marketable firewood.

Hickory Nut Gap and Big Sandy Mush is accepting $99,519 to form a partnership to improve sustainable community forestry through local lumber, small scale sawmills, woodland and medicinal plants, ecotourism, eco-education, land conservation, and the use of local building materials.

Blue Ridge Wild Timbers will use $66,340 to construct dry kilns and develop marketing and education materials to increase capacity for locally sourced firewood while establishing cooperative relationships with unemployed loggers.

Furniture Specialties Inc. is receiving $99,880 to gain Forest Stewardship Council (FSC) certification, conduct seminars, assist local vendors become FSC certified, and market the benefits of green furniture constructed with sustainably harvested wood.

WNC Mushroom Coop is accepting $83,200 to coordinate production of regional growers to collectively market and promote cultivation of gourmet and medicinal mushrooms and sustainably draw from underutilized timber resources to produce mushroom substrate, making this product available to the public.

Highland Craftsmen, Inc. will use $87,550 to certify locally sourced hardwood trees for structural purposes, certify local professionals to provide grade stamping, and provide this service to other businesses.

Recovering Traditional Cherokee Delicacies is accepting $62,327 to train and employ unemployed forest producers to harvest, grow, and market forest food products traditionally gathered by Cherokee tribe members, including wild edible greens and mushrooms.

Smoky Mountain Native Plants is receiving $90,000 to create a network and cooperative of producers to grow, harvest, and market value-added ramp products.

Mountain Valleys RC&D will use $97,800 to train loggers and forest workers to sustainably open old roads and trails in private forests while implementing forest stewardship plans for innovative approaches to forest uses.

(Added by JMD: Three other projects were funded earlier with Appalachian Designs, Bark House Supply Company, and the Boggs Collective).

More information about the projects and economic stimulus effort is available at:

The Southern Research Station, based in Asheville, is providing more than $1.9 million in ARRA funds for the economic stimulus effort being administered by LOSRC. The President signed ARRA into law on Feb. 17, 2009. The Southern Research Station awarded the ARRA grant to LOSRC in a competitive selection process.

LOSRC has awarded more than $1.2 million of $1.974 million in ARRA funds. Of the remaining funding, LOSRC set aside $400,000 in funds for cooperating organizations and technical advisors to provide assistance to grantees. LOSRC will be using $250,000 of the $1.9 million in ARRA funds for project management and assisting grantees. Approximately $115,000 is planned for workshops, meetings, and training for grantees and other forest producers in the WNC community.

(Added by JMD: individuals from the following organizations are cooperating on this project: the NC Division of Forest Resources, focus on timber products, the NC State University Mountain Horticultural Crops Research & Extension Center, will lead the work on non-timber products, the Appalachian Sustainable Agriculture Project, will manage the marketing work, and the Southern Forests Network, will help assemble forest producers interested in sustainable forestry. In addition, there are two dozen technical advisors from across the Southern Appalachians for their expertise.)

LOSRC solicited proposals as part of this economic stimulus effort to help improve the forest products industry in WNC. These ARRA funds were awarded through a “Request for Proposals (RFP)” process. Local companies submitted more than 60 highly competitive project proposals requesting over $4.7 million. The funded businesses met the stringent selection criteria highlighted in the RFPs. Selection criteria included the long-term benefits to WNC forests, primary and secondary community impacts, potential for building local capacity and collaboration, and the sustainability of forest practices.

The marketing project helps businesses to be more profitable as demand for forest products returns and the economy recovers. The stimulus effort provides funding to selected businesses to facilitate collaboration among underemployed or unemployed forest workers. The goal is for forest products companies to expand their businesses, thereby positively affecting the entire production chain, from producers to the consumer.

LOSRC is a non-profit, voluntary association of local governments that manages regional projects and provides services to its members in the areas of planning, economic and community development since 1966.

The Southern Research Station is comprised of more than 120 scientists who conduct natural resource research in 20 locations across 13 southern states (Virginia to Texas). The Station’s mission is “…to create the science and technology needed to sustain and enhance southern forest ecosystems and the benefits they provide.” Learn more about the Southern Research Station at:

Media contact: Erica Anderson (828) 251-6622 or

Insects & Diseases to be on the Alert For

Downy mildew on basil. This picture is taken from Sue Colucci's blog article on the disease at

I was reading an article in the May 2010 issue of the American Vegetable Grower called "A Barrage of Bugs" and it got me thinking of the calls and emails that I have been receiving from growers and agents so far this summer.  Thought I'd give you a short update on what some folks are reporting so you can be on the alert in your own fields:
  • Stink Bugs: reports of problems by both home gardeners and commercial farmers are on the increase.  Stink bugs can make a real mess out of a beautiful crop of tomatoes.  They also are affecting beans, peppers, and cucurbits.  If you are a conventional, commercial farmer there are many insecticides at your disposal that are effective.  Home gardeners and organic farmers don't have as many options.  Pyrethrum based products are sometimes effective.
  • Thrips: in our area the biggest concern is that some species of thrips transmit tomato spotted wilt virus which can destroy your tomato crop.  Conventional growers will find many suggestions for thrips control in the Southeast Vegetable Production  Handbook  Organic farmers will also find control suggestions on various organic websites.  We have had success with the product Ecotec.
  • Late Blight: we don't have it in our area yet, but you should be on the alert for it and keep up with all monitoring that is going on by various universities.  As soon as it is reported in your area, take preventative action on tomatoes and potatoes.  There are many university websites providing good late blight control recommendations for conventional farmers.  Organic farmers, I suggest you look at this article by Alex Stone on eXtension  In our studies in western NC, we had pretty good success holding off late blight last year using Serenade and copper in one spray, five days later applying Sporatec and Neem and then alternating those sprays every five days.
  • Basil Downy Mildew: this is a new disease that you should be watching for. Sue Colucci, area extension agent in WNC, just posted a great article about this disease with pictures and management recommendations on her blog at
  • Cucurbit Downy Mildew: this one will take out your pumpkin patch real quick!  So monitor its progress, it's carried in the wind, on the forecasting service at and learn how to identify it.  See the June NC Pest News for conventional downy mildew control suggestions and the Cornell Resouce Guide for Organic Insect and Disease Management for organic suggestions

Tuesday, July 6, 2010

The Cornell Formula Fungicide: An Example of Why You Need to Check Out Your Internet Information Sources

Last week on the NC Cooperative Extension Horticulture Agents listserv, there was a discussion about homemade fungicides and whether extension agents should recommend them or not.  The infamous "Cornell Formula" fungicide was mentioned as an example.  If you Google "Cornell formula fungicide" thousands of results are presented.  Many of these tell you how to mix up and use this miracle fungicide that was, they claim, developed by Dr. Ken Horst, a pathologist at Cornell University.  Many of the sites come across as credible sources of information.  But look at some of the other results that come up and you will see a discrepency.  Many of those results start out with "Dispelling the Myth of the Cornell Formula Fungicide".  Those explain that there really is no "Cornell Formula" fungicide and that information on an incomplete experiment was distributed over the Internet and has kind of taken on a life of its own.  The bottom line is that the "Cornell Formula" fungicide doesn't work and can actually damage plants.  I have reprinted the press release about that below.  And thank you, Gary Pierce, Harnett County Agent, for bringing that press release to our attention.

My point here is, there is so much "information" available to us now via the Internet.  Anyone can post anything they want to.  You don't have to be an expert to put up a website or blog and start giving out advice.  Please take the time to do a little research, dig a little deeper, find out the qualifications of the person/website providing the information, and check their sources.  In the case of farming and gardening, most always, the information you get from universities, Cooperative Extension, USDA, and professional organizations is valid.  There are also some really excellent personal, small-business websites providing information, too, but amongst them are people with very limited knowledge providing a real mix of fact and fiction.  They often have no professional education or training and/or very limited experience in the area they are professing to be an expert on.  And I've found that some media sources, including radio and television, are also guilty of this.  So check that out next time you turn to the internet for advice.  If you want to learn how to manage late blight on tomatoes, do you want to get that advice from someone who has a PhD in pathology and has been working on tomato diseases for twenty years or from (and this is just an example that I made up) someone with a MBA, who is an expert in business, but just recently developed a passion for gardening and created a website to share his new found knowledge?

By the way, Dr. Ken Horst did go on to get a number of patents for fungicides that are available for home gardeners and commercial growers.  His company website is:

And here is that press release I told you about (as provided on Dr. Horst's H & I Agritech website).  The last few paragraphs are a "sales pitch" for the products sold by the company, but I did not want to edit the press release:

Dispelling the Myth of the "Cornell Formula" Garden Fungicide
Erroneous information has led to the use of ineffective homemade formulas.

Ithaca, NY, February 8, 2006 -- Inconclusive information that originated out of isolated results from scientific trials has found its way into the public domain where it contributes to the myth that concoctions and mixtures of sodium bicarbonate, oil, water and soap are a recommended "Cornell Formula" fungicide. There is no such formula.

"With the advent of the Internet," says Dr. Horst, renowned plant pathologist from Cornell University and President of H & I Agritech, Inc., "The myth of the so-called 'Cornell Formula' continues to spread and I feel that the record needs to be set straight. Many of the formulas that are promoted in articles and forums are simply inferior and may have adverse health and environmental impacts."

Many of these so-called formulas have very limited benefit and some of these recipes can even result in phytotoxicity or burning of the leaves. For example, baking soda and water by itself has limited benefit because it does not spread evenly across the surface of the leaf and easily washes away. The use of oils or soaps to spread and stick the bicarbonate can lead to an unwanted build-up of chemicals, alter soil pH levels and increase the potential of phytotoxicity.

For example, many of the formulas that are repeated on websites, in articles and various publications call for the use of dishwashing soap or other detergents. Adding in soaps that are comprised of a laundry list of chemical ingredients may not be wise. Most soaps now have anti-bacterial chemicals such as Triclosan that could kill necessary bacteria in the soil and may be detrimental to nutrient absorption. Accumulation of these chemicals in or on treated vegetables may not be healthy. Many soaps also have degreasing agents and other chemicals that may not be useful or safe when used as a plant spray.

Stories about the efficacy of baking soda in controlling garden fungi have circulated for many years. Its use is a welcomed alternative to other fungicides because bicarbonates, both sodium bicarbonate and potassium bicarbonate are recognized as safe food additives and do not have adverse environmental impacts. It's no wonder that baking soda-based formulas have been so eagerly passed along among ornamental and organic gardeners.

In 1985 Dr. Ken Horst began research into the efficacy potential of bicarbonates. The research was intended to quantify the true efficacy of bicarbonates, identify their mode of action and determine the most effective use of these compounds.

Several years of research resulted in some significant and surprising discoveries. "The research demonstrated the ability of bicarbonates to effectively inhibit and kill mold spores and determined that potassium bicarbonate was 25 to 35 percent more effective than sodium bicarbonate (baking soda)," says Horst. The research further indicated that a spreader-sticker mechanism was required in order to control and maintain the effectiveness of the bicarbonates. "Without a spreader-sticker," adds Horst, "You don't get complete coverage of the leaf which is necessary to prevent or cure fungal diseases."

During the years of research many spreader-sticker systems were tested, including the use of horticultural oil as an additive. This resulted in better control of the solution and proved more effective than water and bicarbonates alone, unfortunately the test results also showed that horticultural oil as an additive had many negative characteristics.

Negative characteristics of horticultural oil as an additive to bicarbonates include:
*Repeated use for several weeks causes phytotoxicity
*It results in an oily residue building up on the leaves, fruits and vegetables
*There is an occasional visible crinkling of the leaves
*The oil separates rapidly from the water making application difficult
*The use of such an oil may not be ideal from an environmental standpoint; it could increase the hydrocarbon loading of the air and in ground water

For these reasons and others, horticultural oil was rejected as a spreader-sticker. In order to find a safer, more efficient additive, more than 350 spreader-sticker systems were evaluated. Highly effective spreader-sticker additives were discovered which increased the efficacy and reliability of bicarbonates for use on ornamentals, vegetables and fruits. Additional research was done on a wide variety of plants and quantitative results were determined for a broad spectrum of fungal diseases. Ultimately, a combination of spreader-sticker additives in very specific quantities was found to be significantly more effective than all other alternatives.

The patented formula, which is distributed by H & I Agritech, Inc., has been successfully used in commercial and large-scale agricultural settings for nearly 10 years. The same product is also available for use on indoor plants, in home gardens, small organic farming and greenhouse operations under the name GreenCure®.

GreenCure® cures and prevents powdery mildew, blackspot, blights, molds and other plant diseases on garden crops & ornamentals. It is labeled for use against more than 25 different plant diseases including Downy Mildew, Powdery Mildew, Alternaria Blight and Blackspot. It is registered for use on over 85 different annual and perennial flowers, woody and ornamental shade trees, woody and herbaceous ornamentals, many herbs and vegetables, and ornamental nut and fruit trees.

Prevention and control of plant mildew and related plant diseases is of great interest to gardeners. Fungal related plant diseases are damaging and unsightly in ornamental plants and can outright destroy garden crops. In addition, plant molds and their airborne spores can cause allergies and adverse health effects in humans and animals, therefore control of mildew is a serious concern, but controlling mildew the right way is very important.

"It's really amazing how widespread and how often repeated this myth has become." says Horst. "Considering the amount of research that went into finding the most benign and effective solution to control plant mildew, there really is no reason for gardeners to create homemade solutions that may not be effective and may produce unfavorable results."

The active ingredient in GreenCure® is potassium bicarbonate, which is listed by the U.S. Food & Drug Administration (FDA) as generally recognized as safe (GRAS). It is commonly used in foods and medicines and does not have any adverse environmental impacts; therefore the appropriate use of this compound, as a fungicide is an important alternative to many of the conventional fungicides that are undergoing toxicological review by the EPA.

Peter W. Yeager
HR Communicator, Inc.
(Representing GreenCure® and H & I Agritech, Inc.)

Dr. Ken Horst
H & I Agritech, Inc.

Thursday, July 1, 2010

Organic Farming Enhances Biodiversity & Natural Pest Control

I got so excited when I saw this news release from the USDA about one of the studies they've funded on organic agriculture, I just had to reprint it here on my blog where I could easily send people to read it.  This is EXACTLY what so many of us who work in organic agriculture have been trying to tell people.  Now here is a "scientific study" supporting that!  Cool. (the fact that I am an alumni from Washington State University and did my Master's degree on potatoes out there has nothing to do with my enthusiasm for this project :) )

Organic potatoes grown on Jake's Farm in Candler, NC

Researchers Show That Organic Farming Enhances Biodiversity and Natural Pest Control

WASHINGTON, July 1, 2010 – A team of researchers from Washington State University and the University of Georgia have found that organic farming increases biodiversity among beneficial, pest-killing predators and pathogens. In potato crops, this led to fewer insect pests and larger potato plants.

“It’s always been a mystery how organic farmers get high yields without using synthetic insecticides,” says co-author Bill Snyder, associate professor of entomology at Washington State University. “Our study suggests that biodiversity conservation may be a key to their success.”

Ecosystems with more total species, and more beneficial species that are relatively evenly distributed, are thought to be healthiest. The use of insecticides harms biodiversity by reducing the number of species and by making some species (often pests) much more common than others. The study, which was funded by USDA’s National Institute of Food and Agriculture (NIFA) and published in the July 1 edition of the journal Nature, shows that organic farming practices lead to many equally-common beneficial species, and that this reduces pest problems.

In potato fields that used conventional control practices (e.g., applications of broad-acting insecticides), usually just one species of beneficial predatory insect or pest-killing pathogen was common. In contrast, in organic fields several beneficial species were about equally common. Experiments showed that groups of evenly-abundant beneficial species, typical of organic farms, were far more effective at killing potato beetle pests. Because natural enemies are usually more even in organic crops of many different kinds, not just potato, these benefits could be widespread.

NIFA funded this project through the National Research Initiative Arthropod and Nematode Biology and Management competitive grants program.

Through federal funding and leadership for research, education and extension programs, NIFA focuses on investing in science and solving critical issues impacting people's daily lives and the nation’s future. For more information, visit

To view this research highlight online, visit

USDA is an equal opportunity provider, employer, and lender. To file a complaint of discrimination, write: USDA, Director, Office of Civil Rights, 1400 Independence Ave., S.W., Washington, D.C. 20250-9410 or call (800) 795-3272(voice), or (202) 720-6382 (TDD).

This news release is a service of the USDA's National Institute of Food and Agriculture. To view other agency news, visit