Vol. 20, No. 4, May 18, 2005

In this Issue
Plants that can host Asian soybean rust
USDA approves soybean rust funds
Illegal use of sodium cyanide in beekeeping
MSU’s annual economical analysis of agriculture on the Internet
Regional reports
Weather news

Plants that can host Asian soybean rust

Steve Gower
Diagnostic Services

In addition to soybeans, there are a number of forage legumes, beans, weeds and ornamental plants in Michigan that could potentially serve as hosts of Asian soybean rust (Phakopsora pachyrhizi). Worldwide, there are more than 30 species of legumes reported to be hosts of soybean rust in nature and more than 60 species when considering successful inoculation under greenhouse conditions. Many of these host plants are not found in Michigan. For this reason, a list was compiled of plants in Michigan that could be infected with soybean rust (Table 1).

Kudzu (Pueraria lobata) is a weedy legume that infests roadsides, fencerows, abandoned fields and non-crop areas throughout the southeastern United States. It has been described as the “vine that ate the south” because of its aggressive, climbing and trailing habit. Kudzu is a susceptible host of Phakopsora pachyrhizi. Due to the prevalence and location of kudzu, it is believed that this weed will serve as a continual source of soybean rust inoculum for southern soybean growers. The good thing – kudzu is not believed to exist in Michigan.

There are occasions when only a plant genus is listed in Table 1. In these cases, there is not sufficient information on the potential host range of soybean rust in the United States. Keep in mind that other potential soybean rust hosts could be species in the same genera as those listed in Table 1.

It is our goal to make this host list as complete as possible. If you are aware of other “legumes” or “beans” grown in Michigan fields or greenhouses, please contact Steve Gower at 517-432-9693 or sgower@msu.edu

Scientific name

Common name

Coronilla varia

Crownvetch

Crotalaria spp.

Rattlebox

Desmodium spp.

Ticktrefoil

Glycine max

Soybean

Kummerowia stipulacea

Korean clover

Lespedeza bicolor

Shrubby lespedeza

Lespedeza spp.

Lespedeza

Lupinus spp.

Lupine

Melilotus officinalis

Yellow sweetclover

Melilotus spp.

Sweetclover

Phaseolus lunatus

Bean (lima, butter)

Phaseolus vulgaris

Bean, dry-shelled (black, cranberry, kidney, navy, great northern, pinto, small red)

Phaseolus vulgaris

Bean, edible-podded (green, string, snap, wax)

Phaseolus spp.

Bean

Pisum sativum

Garden pea

Senna spp.

Senna

Trifolium incarnatum

Crimson clover

Trifolium repens

White clover

Trifolium spp.

Clover

Vicia spp.

Vetch

Vigna unguiculata

Black-eyed pea

Vigna spp.

Cowpea

The United States Environmental Protection Agency (EPA) and state departments of agriculture have recently been alerted that some beekeepers have been using sodium cyanide compound to control pests in their honeybee colonies/hives. Specifically, apiarists have been purchasing and using a sodium cyanide compound as a fumigant in beehives to destroy or mitigate wax moths including the caterpillar and larvae, as well as to cull out weaker hives. These practices are illegal and have the potential for serious harm to human health and the environment.

All pesticides distributed in the United States must be registered by the EPA. The Federal pesticide law [the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)] defines “pesticide” to include any substance intended for controlling, mitigating or destroying pests. A substance is a pesticide and requires registration as such if the person distributing the substance (1) makes claims, either expressed or implied, that the substance can be used as a pesticide or (2) distributes the substance with the knowledge that the substance will be used to control pests. Any individual selling or distributing sodium cyanide compound for mitigating any pest, including the wax moth, caterpillar and larvae, or any other pest for use in bee hives or colonies is selling and distributing an unregistered pesticide and subject to penalties of up to $6,500 per violation under FIFRA.

Currently, there are no sodium cyanide or similar cyanide compound products registered by the EPA for pest control in honeybee colonies/hives. Also, there are no established residue tolerances for any cyanide compound in honey or beeswax. Honey analyzed and found to contain any cyanide compound residue would be considered adulterated under the Federal Food, Drug and Cosmetic Act and could be seized. The seizure of honey due to adulteration with a highly toxic chemical would be detrimental to the entire apiary industry.

Further, use of sodium cyanide in an apiary setting can be extremely dangerous. The compound is highly toxic to humans and other warm-blooded animals, and it is a Toxicity Category I compound – EPA’s highest toxicity level for pesticides. This rating indicates the greatest degree of acute toxicity for oral, dermal and inhalation effects. It is highly corrosive to the skin and eyes. Cyanide can be absorbed through the skin and its vapor is absorbed extremely rapidly via the respiratory tract.

Beekeepers who are currently in possession of the highly toxic, unregistered sodium cyanide compound or related products should contact their state agricultural agency for instructions on proper storage and disposal of the product. The state agricultural agency can also provide information on registered pesticides, such as paradichlorobenzene and aluminum phosphide products, that are legal to use to mitigate pests in honeybee colonies/hives.

MSU’s department of Agricultural Economics 2005 Annual Agricultural Outlook is available on economist Jim Hilker's web site at: http://www.msu.edu/user/hilker

Regional reports

1 - SW Michigan Research and Extension Center

Ron Goldy

Weather
We’ve had slightly below to normal temperatures with highs ranging from 53^o to 75^oF and lows ranging from 42^o to 49^oF at SWMREC. Precipitation ranged from 0.5 to 1 inch.

Commodity reports
Field preparation continues but dry soils have hampered bed shaping, fumigating and plastic laying. Many growers are going ahead with plastic laying despite the dry conditions since they are unable to wait for rain. Transplanting and seeding of crops continues.

Asparagus harvest continues with few reported problems.

Tomato transplanting has picked up now that the frost threat has diminished.

Cucumber and squash transplants in tunnels are at the 3 to 4 leaf stage. Direct seeded are at the cotyledon stage.

Pepper and eggplant transplanting is scheduled for later this week or early next week.

Sweet corn is 3 to 4 inches tall and looking quite pale, most likely due to cool temperatures and dry soil.

Amy Irish-Brown

Commodity reports
Radish planting continues with first plantings starting to emerge

Lettuce crops are in various stages of growth depending upon planting date and method.

Cabbage is doing well.

Celery is developing nicely. Some injury was reported from the freezing temperatures two weeks ago, but plants are growing out of it.

Early planted sweet corn is starting to emerge.

Vine crop seeding and transplanting should be starting at any time if not already.

Tomato transplanting began last week after predicted frosts late in the week went by.

Transplanting of peppers has just begun as well.

Norm Myers

Weather
Temperatures for the past week continue to be slightly below normal. Some frost occurred on Monday morning (May 16) but the frost predicted for Tuesday morning did not occur. General rainfall in the area during the past week was in the one-inch range.

Commodity reports
Carrot planting is completed except for a couple of growers who are scheduled to plant through the end of May. Stands are reported to be very good at this time.

Spinach plantings continue to look good also. The last plantings are at small 2-leaf growth stage.

Ground is being prepared for snap beans and squash planting that could commence in another week to 10 days with favorable warm weather and soil conditions.

Jim Breinling

Weather
There was some patchy frost here on Monday morning (May 16), but the damage was minimal. There were no reports of frost anywhere in Oceana County Tuesday morning. We did receive almost an inch of much needed rain in several small rains late last week.

Commodity reports
Growers picked their asparagus fields down very heavily on Monday in preparation for a frost Tuesday morning. While cloud cover prevented any frost, it will take a couple of days of warm weather to let the asparagus grow enough for another harvest. There was some frost damage on Monday morning in the northwestern quadrant of the County, but nothing that couldn’t be picked through. I am already getting reports of a flush of weeds coming on since last week’s rains, and I anticipate more as weather warms. Pest problems so far have been minimal with only a little cutworm damage reported and only a few common asparagus beetle adults or eggs showing up. Warm weather may change that.

Growers are reporting excellent stands of carrots. Some growers are worried that the stands may even be too good. Barley cover crops are now large enough that they should provide pretty good wind protection. Last week’s rains should have done a good job of incorporating pre-emergent Lorox weed control sprays. Irrigation continues in spite of some rain last week.

Sweet corn for local farm markets is going in most areas. Growers for roadside stands and farm markets will now begin setting out transplants.

Hannah Stevens

Commodity reports
There is no reported pest activity at the time, although growers should be watching for flea beetle activity on cruciferous crops. Seeded cool season crops are growing well although transplants of these crops may have experienced some frost injury. Any warm season crops that were not protected by row covers are at risk from frost.

First seedings of sweet corn are now at about one inch tall but emergence has been reported as irregular.

Jeff Andresen
Agricultural Meteorology
Geography

Upper airflow across the Upper Midwest is expected to gradually shift from the ridging pattern currently in place to a troughing pattern by early next week, which should allow for at least a temporary moderation of temperatures to normal levels. An area of low pressure over the northern Great Plains Wednesday morning (May 18) will move southeastward to the eastern Ohio Valley by Friday morning, bringing a period of unsettled weather to Michigan. Showers and a few thundershowers are expected with this weather system beginning Wednesday in western sections of the state continuing through early Friday morning.

Rainfall totals are expected to remain in the 0.25- to 0.50-inch range or less with best chances for precipitation across western and southern sections of the state (some northeastern sections of the state will likely remain dry). Fair and dry conditions are expected Friday through the majority of the upcoming weekend with the next chance for rainfall late Sunday evening or Monday of next week. Temperatures will slowly warm from highs ranging from the 60s Wednesday to the upper 60s to low 70s Friday through Sunday. Low temperatures will range from near 40 in the north to the low 50s south Thursday morning, warming to low 40s north to near 50 south by Friday. Cooler temperatures are likely again for the first half of next week.

In the medium range time frame, latest forecast guidance calls for a return of upper air troughing across the Great Lakes region and a ridging pattern across the western United States. The NOAA Climate Prediction Center 6-10 day and 8-14 day outlooks (for May 23-27 and 25-31) both call for temperatures to fall back to below normal levels. Precipitation totals during the 6-10 day period are forecast to increase to a range of near normal in western sections of the state to above normal levels in the east. Near normal precipitation totals are expected in the 8-14 day time frame. Climatological normals for the third week in May include ranges of high temperatures from the low 60s north to the low 70s south and lows from the low 40s north to the upper 40s south. Normal weekly precipitation totals range from about 0.65 inches across northern and eastern sections of the state to about 0.75 inces in far southern sections of Lower Michigan and in western sections of the Upper Peninsula.