The New Agriculture Network's on-line newsletter with seasonal advice for field crop and vegetable growers interested in organic agriculture.

Vol. 2, No. 6 - July 14, 2005

In this issue today

	Soybean update for organic farmers
	Aphid sucker is in business
	Research finds predators suppress soybean aphid in some Michigan fields
	Purdue field events update farmers on soybean rust
	Keeping up with soybean rust
	Reports from organic growers

Next issue will be posted July 28. Read previous issues through our calendar of issues.

Soybean update for organic farmers
Prepared June 27 by Kathleen Delate
Iowa State University

The Organic Management of Asian Soybean Rust (OMASR) project, coordinated by Iowa State University, has been established to identify and test best management practices for control of Asian Soybean Rust (Phakopsora pachyrhizi) (ASR) in organic production and to determine how areas infected with soybean rust in South America and Africa are dealing with ASR in organic systems (see description of ASR in http://www.plantpath.iastate.edu/soybeanrust/.) Asian soybean rust, which arrived in the U.S. in 2004, has the potential to be the single most important impediment to economical organic production in the U.S., with the economic impact of ASR in organic systems ranging from $30 to $120 million in yield loss, in the event of its arrival in organic soybean areas.

The spread of ASR this 2005 season has, fortunately, been less than estimated from original computer models. As of June 26, 2005, soybean rust has not moved beyond Georgia and Florida, but experts warn that July and August storms and hurricanes have the potential to bring ASR spores into the Midwest before the end of the season. The tradeoff between dry weather (that does not support spore dispersal and pathogen growth) and adequate yields continues to be on everyone's mind, as some eastern organic soybean areas enter their third week without rain.

Research plots established at the University of Florida Quincy Research Station (where ASR was discovered in October 2004 in senescing soybeans) remain free of the disease at this time. Organic treatments that will be tested in these plots include National Organic Program (NOP)-compliant fungicides, such as copper sulfate and hydrogen peroxide, and biological controls, including Bacillus pumilis (BalladJ) and other mircrobial products. System effects for management of soybean rust, including extended crop rotations and windbreaks (to mitigate spore dispersal), will also be investigated once ASR moves into organic growing areas.

In addition to our research plots in Florida, several organic farmers in Iowa, Michigan and Pennsylvania are testing a commercial formulation of Bacillus pumilis (BalladJ, AgraQuest, Inc., Davis, CA). These trials will be used to test control of ASR if the disease arrives this year, but also for other minor soybean diseases, such as Cercospora. The mode of action of this natural bacterial product consists of several mechanisms, including setting up a competitive field against harmful fungi on the leaf surface. To date, we have no data on ASR control with any organic product in the U.S., and until our trials are completed, we are not recommending any one control treatment over another. AgraQuest data from South Africa show a reduction of ASR with BalladJ from an initial infection rate of 46.3% down to 43.8%. In another study in South Africa, ASR levels were reduced from 0.0075% to 0.0025% with BalladJ. Whether we will see this level of control in U.S. plots, and whether this level of reduction warrants the expense of spraying materials, will be determined through our research.

Crop insurance for those using “good organic farming practices”
Crop insurance should cover organic farms in the event of ASR arriving in your field this year, if you are using "good farming practices" by following normal certified organic practices, including crop rotation and weed management (i.e., doing everything to bring the crop to harvest). Information is contained on the USDA-Risk Management Agency (RMA) website: http://www.rma.usda.gov/news/managers/2005/pdf/mgr-05-010.pdf.
You should be enrolled with an agency that is covered by federal crop insurance. If you intend to spray any material on your soybean crop, you must notify your certifier and include information on the product in your organic farm plan. You should also connect with your certification agent or Extension agent familiar with organic practices and review procedures to identify and report any suspicious leaves and the program you will follow should ASR arrive in your area. ISU has established a First Detector system, where individuals, including members of the Organic Ag Program, have been trained to identify ASR. As required of all certified organic producers, the log you keep of all your practices for your organic certification may also be used in the event of any insurance claim.

Monitoring system and best management practices for organic growers
We have received support for studying various organic tools through the USDA-CSREES office, and logistical support from the USDA Office of Pest Management. The Organic Trade Association has also requested of the soyfoods industry support for the OMASR project. Through this project, we will create a strong national network for ASR monitoring and delivering best management practices for managing ASR in organic systems. We will post various updates and also provide updates on insect pests affecting organic soybean fields this year. To date, bean leaf beetles (BLB), which vector the bean pod mottle virus (causing staining and a downgrading of organic food soybeans to feed quality) have been seen in some organic fields this year. The beetles are currently entering their first generation in Iowa, the over-wintering population causing some damage to green beans and earlier-planted soybeans in May and early June. The prediction in Iowa is that BLB will be more of a problem than last year, but not as problematic as the beetles were in 2003. Organic bean leaf beetle control tactics research was not conclusive after four years of ISU trials, suggesting that BLB management will include planting soybean varieties that can be sold as feed beans, where seed staining is not an issue (see webpage http://extension.agron.iastate.edu/organicag/rr.html (under Neely-Kinyon Farm and "Soybean Staining Experiments").

Soybean aphid options
As for soybean aphid, a pest that can cause yield loss if populations become excessive, these pests have also been seen this year in Iowa, but it is too early to tell if any treatments are warranted. In trials conducted through the Iowa State University Organic Ag Program, several NOP-compliant insecticides were effective in managing soybean aphid, particularly neem-based products. Despite the dislike for multicolored Asian lady beetles, a nuisance in homes and on bearing fruit crops, these beneficial insects, along with other predatory lady beetles, consume vast quantities of soybean aphids. Spraying any insecticide (organic or conventional) may have a detrimental effect on beneficial insect populations, although the effect will be more damaging with conventional sprays. (See separate article in this issue about predator impacts on soybean aphid.)

As practiced by all organic farmers, monitor your fields daily and report any suspicious leaves or insects. "Working with Nature" is the motto of organic farming, so ecologically-based strategies will be developed to allow organic farming to prosper and grow.
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Aphid sucker is in business

Christina DiFonzo, Entomology, Michigan State University

The year 2005 was predicted to be a heavy year for soybean aphids. That prediction came from Dr. Dave Voegtlin, an entomologist with the Illinois Natural History Survey. Dr. Voegtlin runs a series of suction traps across Illinois to sample migrant aphids flying in the landscape. Over the past four years, counts of the soybean aphid in the Illinois suction traps in the fall have reflected the observed population of soybean aphids in the field the following season. This data is at: http://www.ipm.uiuc.edu/fieldcrops/insects/soybean_aphids/
suction_trap_network/index.html

Dr. Voegtlin’s findings of heavy movement in the fall of 2004 were backed up by buckthorn sampling in late fall, which showed numerous eggs. This spring, we experienced heavy colonization of SBA moving from buckthorn to soybeans – so the prediction was correct for 2005.

Suction traps are one of the most unbiased sampling methods for aphids. They do not rely on aphid behavior to catch the critters (like, for example, yellow sticky traps). Instead, they suck in a certain amount of air in a given amount of time; the aphids in that air are captured in a bottle at the base of the trap. Trap catches can be directly compared from place-to-place and time-to-time. The traps are relatively easy to operate – they simply plug into a power source and run continuously, with the sampling bottle changed each week. The real challenge comes in sorting and identifying the trap catch.

Based on the success of the Illinois state network, this summer the field crop entomologists in several Midwest states expanded the network to a regional level to monitor movement of the soybean aphid and other agriculturally important aphids (including species that transmit viruses in vegetable crops). The traps were built by the University of Illinois and distributed to surrounding states by Dr. Voegtlin. The following states are now running multiple traps for the Network: Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota and Wisconsin. In Michigan, the traps are located at the Kellogg Biological Station, at the MSU Entomology farm on campus and at the MSU Bean and Beet Research Farm (photos). Each state is responsible for maintaining the traps, changing the sample bottle and sending weekly samples in for sorting and identification to the Voegtlin lab at the Illinois Natural History Survey.

Updates on soybean aphid in Michigan are available at: http://www.ipm.msu.edu/soybean/aphid.htm

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Mary Gardiner and Doug Landis, Entomology, Michigan State University

Depending on where they farm, some Michigan farmers may have observed soybean aphid numbers increasing, decreasing or remaining about steady. What factors are responsible for these fluctuations? As part of a multi-state study of soybean aphid IPM, we are sampling soybean aphid and its natural enemies in four fields in Kalamazoo, Saginaw and Gratiot counties. On June 28 we observed aphid populations reaching as high as 173 per plant in one Kalamazoo County field. However, the following week (July 5) populations in the same field declined to less than 70 per plant.

To understand if predators are the cause of soybean aphid decline, we compared aphid populations on plants open to predators versus plants caged to prevent predators from eating aphids. On the caged plants, aphid populations increased from 10 aphids per plant to 784 per plant in two weeks (View cages and catch data). While on the open plants, predators maintained aphid populations below 100 per plant over the same two-week period. The most common predators collected in the Kalamazoo County field were the seven-spot lady beetle, multi-colored Asian lady beetle and minute pirate bug. This field averaged 0.6 predators per plant on June 28.

Despite what seems like a small number of predators per plant, natural enemies are impacting aphid populations in this field. By comparing aphid populations in cages excluding predators with plants open to predation, we have shown that the decline in aphid numbers from June 28 to July 5 is due to predators consuming soybean aphid. The caged and open plants were in the same field and subjected to the same environmental conditions, ruling out rainfall, weed control or other cultural practices as the cause of aphid reduction. Therefore, if you are seeing aphid populations in your field level off or begin to decline, you may want to wait to spray to see if predators can maintain this pest below the 250 aphids per plant threshold.
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Purdue field events update farmers on soybean rust

by Steve Leer, Purdue University, 765-494-8415, sleer@purdue.edu

A Brazilian plant pathologist with an extensive background in diagnosing and treating Asian soybean rust will share his knowledge with Indiana soybean growers during four special field events July 18 and 19. The Soybean Rust In-The-Field Updates are free and take place at Purdue University agricultural research farms in Tippecanoe, Randolph, Jennings and Knox counties.

Tadashi Yorinori of Brazil's National Center for Soybean Research, commonly known as Embrapa Soybean, will discuss management strategies for controlling the fungal disease. Soybean rust was first found in South America in 2001.

”Fungicide, the only known option for controlling rust, is among a handful of topics Yorinori and Purdue Extension specialists will address during the field events,” said Jim Beaty, superintendent of Purdue's Agronomy Center for Research and Education (ACRE).

"We'll try to answer these questions: 'Is soybean rust in Indiana?' 'Did rust spores come up on Hurricane Dennis?' 'What are the Purdue sentinel plots showing?' 'Will I need a second fungicide spray?' and 'When should I apply that second spray?'" Beaty said.

"Tadashi has a great deal of experience with soybean rust in Brazil and is known throughout that country for his Extension work," said Greg Shaner, a Purdue Extension plant pathologist who will join Yorinori on the statewide tour.

Soybean Rust In-The-Field Updates will take place at the following times and locations:

• July 18, 9-11 a.m. -- ACRE, 4540 U.S. 52 West, West Lafayette, Ind.
• July 18, 3:30-5:30 p.m. -- Davis-Purdue Agricultural Center, 6230 N. Indiana 1, Farmland, Ind.
• July 19, 9-11 a.m. -- Southeast-Purdue Agricultural Center, 4425 E. County Road 350N, Butlerville, Ind.
• July 19, 3:30-5:30 p.m. -- Southwest-Purdue Agricultural Center, 4669 N. Purdue Road, Vincennes, Ind.

The field events are sponsored by Purdue's Department of Botany and Plant Pathology, and Purdue Extension. No advance registration is required. For more information, contact a local office of Purdue Extension or the toll-free Purdue Extension hotline at 1-888-398-4636 (EXT-INFO). Additional information about soybean rust is available on the Purdue Plant and Pest Diagnostic Laboratory Soybean Rust Web Page, at:
http://www.ppdl.purdue.edu/ppdl/soybean_rust.html.
     
Sources
Jim Beaty, (765) 463-2632 jbeaty@purdue.edu
Greg Shaner, (765) 494-4651, shanerg@purdue.edu

Related web sites
Purdue University Plant & Pest Diagnostic Laboratory soybean rust page:
http://www.ppdl.purdue.edu/ppdl/soybean_rust.html
Purdue Agricultural Communication soybean rust page:
http://www.agriculture.purdue.edu/soybeanrust/
Indiana rust update web site:  www.ppdl.purdue.edu/ppdl/SBR/SBR_IN_update.htm

National Hurricane Center: http://www.nhc.noaa.gov/

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Keeping up with soybean rust

Joy Landis
MSU IPM Program

Here is a compilation of some key links for soybean rust information and updates at our sponsoring universities:

Purdue University
www.ppdl.purdue.edu/ppdl/SBR/SBR_IN_update.htm

Michigan State University
http://www.ipm.msu.edu/soybean/rust.htm

University of Illinois
http://soyrust.cropsci.uiuc.edu/index.cfm?id=diag

Iowa State University
http://www.plantpath.iastate.edu/soybeanrust/

USDA information site with monitoring update
http://www.sbrusa.net/ 

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Reports from organic growers

Southeast Michigan – John Simmons
Consistently hot weather is advancing crop stages rapidly. Corn and sunflower fields are across the rows. Soybeans are filling the rows. Early sunflowers are approaching bloom. Early short-day corn is starting to tassel. Winter barley is being harvested. Spelt has turned color and is in the dough. Oats are starting to turn color. Rye has turned. Some organic soft white wheat has been harvested at 17 percent moisture. First cut hay was finally harvested and is tan colored with considerable leaf loss. Scattered rains have spurred crop growth and slowed/browned hay harvest. MSU aphid scouts found 20 aphids per plant average in my soybean field; the field is in early bloom.

Row cultivating of corn, soybeans and sunflowers is now complete. Currently, we are harvesting winter barley. We are also mowing Canada thistle patches in small grains and in seed clover fields. Another task is preparing buckwheat fields. In the next two weeks we will be planting buckwheat and clover, preparing for small grain harvest and probably starting spelt harvest. I’m interested in the latest on soybean aphid control and the soybean rust reports.

Southeast Michigan – Rob Malcomnson
Hot weather has accelerated crop growth. Frequent thunderstorms have delayed hay cutting.

Currently, we are cultivating the last of the beans, harvesting first cut hay and picking vegetables.

In the next two weeks we will harvest the second cutting of hay and vegetables.

Indiana
South Central Indiana – Dale and Sandra Rhoads
We have had dry and warm conditions until this week. We are now experiencing light rains—only the second light rain this entire year, everything else has been heavy thunderstorms. (Incidentally, this weather pattern fits right into the latest computer models of how global warming will affect the Midwest, i.e. storms being more violent as one of the components.) With the temperatures staying under 90 degrees, we are still able to harvest spring-like crops that will slow down if the weather heats up more.

We started doubling the size of our salad greens plantings in anticipation of hot weather. By doubling the size, we offset poorer germination, quicker bolting of the plants and better taste by having a shorter life in the field.

Temperatures are staying cool enough that Galisoga continues to be our largest weed problem as its germination seems to slow down with higher temperatures.

Currently we are staying up with our regular salad greens plantings, weeds harvesting, etc. We are also tying up tomato plants as they are growing 4 to 6 inches per night. Weeding pressure has been high in salad greens. We’re doing some maintenance-type mowing and maintenance-type activities now that the big spring rush is over and we’re working only 10 hour days. Having to do Bt applications to tomatoes and kale for worms. We are harvesting tomatoes, squash, salad greens, kale, chard, parsley and dandelion greens. First sweet corn should be starting soon.

We’ve been doing some educational marketing with the produce manager at one of the stores we deal with. He is starting to spread things out with too many farms and not needing what he told us we should grow for him. With another product of ours, he cut orders due to some mistakes on their end. We have about eight young produce managers -- funny that part of our job is educating younger “organic enthusiasts.”

We’ve been trying to control leaf spot on Swiss chard with copper applications and it is having some beneficial affect. It appears to us that we now have about 50 percent less disease and are still able to harvest significant amounts compared to last year.

First signs of stink bug on Asian pears have shown up so we need to do a Surround application on trees. During the next couple of weeks we will be keeping up with regular rotations of tilling, weeding, planting and creating stale seed bed for salad greens. More maintenance mowing -- this year we are mowing twice–March and July. We will also continue to harvest. This is our slow time (ha ha) and we will be doing some maintenance as time allows. Another task will be to planting some cover crops (buckwheat) in some unused areas.

In our fruit crops, plum curculio got 90 percent of the Japanese plum harvest. It appears at this time that 50 percent of European plum harvest with be sting free. Apples and pears were hit at about 50 percent. Asian pears at this time appear to be sting free except for one row that I cannot tell yet. Asian pears are starting to show some stink bug and Surround applications will stop that.

I have no experience with this site but wanted to share this organic seed source for consideration.

Plant stock and organic seed sourcing service (free service for 2005): Courtney Guido, 49 Circle D Drive, Colbert, GA 30628, 706-788-0017, http://www.savingourseed.org/, sourcing@savingourseed.org

Southeast Indiana – Gary Reding
We have finally received a little rain from Hurricane Dennis. We had about .35 inches yesterday and again this morning. Popcorn is looking good despite the dry weather and heat from the past several weeks. It just started rolling on small hillsides and isolated portions of the fields. The conventional corn in our area has been rolling for two weeks and some of it is becoming very uneven. I attribute the drought tolerance and rapid growth rate to the previous crop of pasture. The organic matter in the soil is retaining what small amount of moisture the rains provided earlier.

Organic soybeans after first cutting of hay are spotty in one field due to dry planting conditions. Maybe this rain will bring the rest of them out of the ground.

In the past couple of weeks, we finished cultivating the slowest growing field of popcorn and rotary hoed soybeans. We still have to cultivate the beans now that it has rained. Weed control seems to be quite good to date. Pigweed and giant ragweed are predominant pests in the popcorn and just a few spots of grass in the soybeans. We will continue to graze on the remaining pastures and possibly bale some third cutting hay soon if the rain holds out. I do intend to plant spelt in the fall.

We also have been making compost lately, but the dry weather has slowed that process down some. We started to haul some water to the piles, but find it somewhat cumbersome. We still need to work on our technique in this venture.

Our county fair is this week and one individual asked if I was seeing the large cracks in the ground that he had in his pastures. I told him I had not and that I could still step in fence posts fairly easy. This is due to the managed grazing instead of set-stocking of my pastures. Hopefully this rain will be enough to encourage new growth in the pastures and the crop fields. So far, insects are a non-issue in my fields.

Iowa
Northwest Iowa – Paul Mugge
Weed control has been difficult in corn and soybeans due to continuous rains through June.  It seems like we have a rainfall the day after cultivation, which keeps the weeds growing.

Triticale is about ready for harvest and the weed control in these fields is excellent.  We expect excellent yields this year.

Flax is growing well, however, very weedy.

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