Poncho replant restrictions - know the label |
Some early-planted cornfields may have been drowned out by the recent rains and need to be replanted. If a field was previously planted with Poncho-treated seed, the label does have some important plant-back restrictions. These restrictions hold true for both Poncho 250 (low rate) and 1250 (rootworm rate). Many growers I talk to have not read or do not recall getting a label with their Poncho-treated seed, so this may come as a surprise. §
Corn, canola, rape-seed: immediate replant §
Cereal grain, grasses, non-grass animal
feeds, SOYBEAN, DRY BEANS: 30 DAYS § All other crops: one year! § To
get a copy of the Poncho label visit this web site: |
Expect potato leafhopper soon |
Although I have heard no reports of potato leafhopper (PLH) yet, PLH generally arrives in Michigan over the next several weeks (see accompanying list). PLH does not overwinter in Michigan, so it is not dependent on degree-day accumulation across the state. Instead, adults are carried north on wind currents, often associated with rain events. Bottom line - remember to think about scouting for PLH after first cutting. Date of first report of PLH 1995 - May 18 2000 - May 18 1996 - May 23 2001 - May 17 1997 - May 22 2002 - May 22 |
Watch for cutworms and armyworm |
Black cutworms can devastate field crops, especially when plants are small. Adult black cutworms (moths) migrate into Michigan in early spring; crop damage sometimes occurs by mid- to late May. Extension personnel in Indiana and Illinois report heavy catches of cutworm moths, and these moths are heading north. Before the crop emerges, adult moths lay eggs on available vegetation. This includes plants along field margins and ditches, cover crops within the field and especially in areas with low, densely growing weeds. When the weeds or cover crops are killed by herbicide, larvae move onto the nearest green plants - the crop. Small larvae initially feed aboveground, making small pinholes in the leaf or chewing on the leaf edges. Larger larvae move down and feed near or below the ground, cutting off plants at the base. Cut plants are wilted or simply dead. Effective weed control avoids or reduces black cutworm infestations. Controlling low-lying, densely growing weeds such as chickweed, deadnettle, and mustards reduces the areas for egg-laying by female moths. If weeds or a cover crop can be killed a week or two before crop emergence, most cutworm larvae will starve. Over the last few years, there have been cutworm problems in corn, beans and sugar beets, perhaps because of earlier planting or changes in production practices to no-till. Also, there has been a large increase in Roundup Ready crops, so fields may be weedier early in the season. Scout for cutworms at seedling emergence. Look for wilted or cut plants, and dig around the base of nearby seedlings to find the larvae. If you can't find a cutworm, move down the row to the next apparently undamaged plant. Larvae feed at night and hide during the day, so the best time to look for larvae is in the morning. A general threshold is 5 percent or more of plants showing cutworm damage. Rescue (foliar) insecticide treatments are the preferred way to manage cutworm because few fields will have a significant problem. Insecticides are most effective if sprayed in the evening when the cutworms are active. In crops like corn, beans and alfalfa, pyrethroids such as Ambush, Baythroid, Mustang, Pounce and Warrior are particularly effective against cutworms (Check labels for specific crop registrations and rates.). For sugar beets, options include Asana, Declare, Lorsban, and Mustang. For good pictures of black cutworm damage in corn, visit: http://www.ent.iastate.edu/imagegal/plantpath/corn/bcutworm/ Like black cutworm, armyworm moths prefer to lay eggs in areas of heavy vegetation. This includes weedy fields, fields with a cover crop and small grains such as wheat. Also, parts of fields bordered by ditches, fencerows and small grain fields are at risk. On corn, larvae eat the leaves, giving the plant a tattered appearance. In severe infestations, only the leaf midrib is left. Another sign of armyworm is large cylindrical pellets of frass (insect excrement) in the whorl. Larvae feed at night; during the day, they hide near the base of plants, or down in the whorl. In wheat, larvae feed on the leaves and also may clip heads. As small grains mature and dry down, larvae sometimes march en masse into neighboring fields (thus the name "army"). For corn, the threshold is one or more larvae per seedling; at whorl stage, 25 percent of plants with two or more larvae per plant or 75 percent of plants with one larvae; five or more per plant in tassel-stage corn. For small grains, treat if there are four or more larvae per foot of row. In all cases, spray on if larvae are less than 1.25 inches - larger larvae are near pupation and will not feed for much longer. Infestations tend to be at field margins, so treating a partial field is often an option. Check labels for insecticide rates. For good pictures of armyworms and armyworm damage, visit: http://entomology.unl.edu/images/smgrains/armyworm/armyworm.htm |
Don't forget AMS with glyphosate |
Many
commercial glyphosate products are currently marketed in Michigan.
The main difference among the many available products is the surfactant
component of the formulated products; some may need additional surfactant
while others do not (See Table 10, p. 137 of Extension bulletin
E-434). However, ammonium sulphate
(AMS) should always be added to all glyphosate products
in order to minimize the negative effect of hard water on glyphosate
activity. The addition of AMS is especially important for velvetleaf
control with glyphosate, regardless of water quality. Dry AMS should
be spray grade and applied at 17 lbs/100gal. Liquid AMS products
are equally effective if applied at a rate equivalent to 17 lbs/100gal. There
are also many AMS substitutes on the market. These products typically
contain some AMS, however, the amount of AMS varies widely among
products. When added according to the product instructions, the
amount of AMS in many AMS substitutes is much less than 17 lbs/100
gal. MSU has tested some, but certainly not all, of the current
commercial products. This research has shown that the most effective
AMS substitutes are those that contain the most AMS. Some AMS substitutes
were ineffective at overcoming hard water antagonism and none of
the products tested at MSU have been superior to AMS at 17 lbs/100
gal. Recommendation: Always add AMS at 17lbs/100 gal. with
all glyphosate products. |
Managing scab (fusarium head blight) and other diseases on wheat |
A
Section 18 exemption request for the use of Folicur on Michigan
wheat has been granted by the EPA. Because only one application
of Folicur is allowed, and Michigan recommends a single yearly fungicide
application to manage all wheat diseases, application of Folicur
should be delayed at least until the initiation of anthesis (flowering)
to determine if there is a potential for scab to develop. A national
and state risk map can be found at: This map includes Michigan and surrounding states. Examine the map now for details on what parameters you will need to input in order to get the most out of the map. Start assessing this map as the wheat begins to head. Carefully follow the directions to determine the risk for scab to develop. Note that the potential around weather stations can be assessed by clicking on an individual weather station. Most
of the wheat varieties grown in Michigan are moderately to highly
resistant to powdery mildew and rust but susceptible to scab. Fungicides
are not economical for the management of powdery mildew and rust
on most of these varieties but can be beneficial on a highly susceptible
variety. Unfortunately, variety resistance can be overcome by changes
in the populations of the powdery mildew and rust pathogens. Therefore,
it can be important to scout fields for the early detection of these
diseases. More information on managing wheat diseases, including
a table that provides guidelines for the use of fungicides, can
be found at: The accompanying table lists fungicides registered in Michigan for wheat. If there is a perceived need to apply a fungicide prior to anthesis, use one of the fungicides listed in Table 1, and save the single application of Folicur in case the potential for scab is high. The important points in the Folicur
section 18 are: 2. A maximum of 250,000 acres of wheat in Michigan may be treated. 3. Application may not be made within 30 days of harvest. Straw cut after harvest may be fed or used for bedding. 4.
This specific exemption expires June 25, 2004. (NOTE: In most years applying at this late date will exceed the 30 days
to harvest limitation. Folicur should be applied within one 7 to
10 days of the beginning of flowering). 5. Residues of tebuconazole per se are not expected to exceed 0.05 ppm in wheat grain, 15 ppm in or on wheat hay, and 2 ppm in wheat straw as a result of this Section 18 use. Combined residues of tebuconazole and its HWG 2061 metabolite are not expected to exceed the following levels in animal commodities as a result of this use; 0.2 ppm in cattle, goats, horses, hogs, poultry and sheep meat-by-products, and 0.1 ppm in milk. Time-limited tolerances in connection with this FIFRA Section 18 emergency exemption have been established for residues of tebuconazole on wheat commodities at the aforementioned levels. These time-limited tolerances currently expire and are revoked on June 30, 2005. The existing tolerances in 40 CFR §180.474 for wheat grain, milk and meat byproducts are sufficient to cover residues expected from this emergency exemption use. Table 1. Efficacy of fungicides for wheat disease control based on appropriate application timing.
* The greater the
number of + signs the greater the relative efficacy. ** (+) Indicates
greater efficacy at higher application rates. *** Folicur does
not have a federal label, but may have Section 18 emergency registration
in some states, including Michigan. 1Not recommended for scab. Uses strobiluron chemistry
which may increase levels of vomitoxin in wheat grain. Quadris has
a 45 day pre-harvest interval (PHI) for application. Headline has
a 14 day PHI. Stratego has a 30 day PHI. Quilt can be applied up
to Growth Stage 9. Tilt and Propimax
are recommended at 4 oz/a no later than Feekes growth stage 10.5,
which is the beginning of flowering (anthesis). Do not graze or
feed forage, fodder, or straw from rotational crops planted in the
fall or the spring following treatment. Do not graze or feed livestock
treated forage or cut the green crop for hay or silage (wheat, barley,
rye). After harvest, the straw may be used for
bedding or feed. Make only one application per season. This information is provided only as a guide. It is the responsibility of the pesticide applicator by law to read and follow all current label directions. No endorsement is intended for products listed, nor is criticism meant for products not listed. |
Harvest alfalfa on time to get top quality forage |
The first cutting of alfalfa is nearing in Southern Michigan. It is critical for growers to harvest the first cutting in a timely manner. This will help to obtain their goals for quality forage. Delaying cutting of first harvest beyond the optimum stage of growth for high quality results in more money spent by dairy farmers on costly supplements to off-set poor forage quality. In addition, the cows will not milk as well. When (GDD) base 41F accumulates to 750, alfalfa contains approximately 40 percent Neutral Detergent Fiber (NDF). Farmers, who use this method generally start harvesting earlier, resulting in high forage quality for their dairy herds. Based on research at Michigan State University (2), alfalfa averages 40 percent NDF at about 750 GDD. An NDF concentration of 35 percent is approximately equivalent to 600 GDD. It takes a total of about 970 GDD to reach 45 percent NDF. The first cutting is the most important harvest for alfalfa as it often represents up to 30 to 40 percent of the total yield for the year. Optimum forage quality for dairy cows is reached in alfalfa fields when the (NDF) content averages 40 percent. Farmers who are storing their alfalfa in horizontal structures should begin harvest when their alfalfa is about 38 percent NDF depending on how quickly they can complete their harvest. For those farmers who are growing alfalfa for a cash crop, harvesting hay, which is near 40 percent NDF, will command a higher price and be easier to sell than that harvested more mature. Another method of determining forage quality of alfalfa in the field that has been shown to be an accurate method is called the Predictive Equation for Alfalfa Quality (PEAQ). The PEAQ method, developed at the University of Wisconsin, uses the longest stem and the most mature stem in an alfalfa sample to estimate neutral detergent fiber (NDF) content of the forage in the field. The results of this equation has been modified and printed on the sides of wooden sticks called "PEAQ sticks." The sticks are calibrated to read NDF units directly off the stick. These sticks take a lot of the busy work in estimating quality from a spreadsheet to just reading the NDF units from the side of the stick in the field. Most Extension offices have these sticks. While obtaining PEAQ estimates of NDF, producers can scout their alfalfa fields for winter injury, disease development, insect damage and weed encroachment (4). Good sampling technique is critical to ensure reliable NDF estimates. It is important to obtain NDF estimates using the PEAQ method at five or more locations across the field. As with GDD, the PEAQ method was developed for pure stands of alfalfa. NDF estimates from PEAQ will not account for weeds or grasses in the stands. PEAQ is not reliable for estimating NDF when alfalfa is very short (longest stem less than 16 inches) or very tall (longest stem more than 40 inches). This PEAQ stick method can be
used by following the steps Step 2: Using the PEAQ stick, measure the length of the longest stem in the 2-square-foot area. Measure it from the soil surface (next to plant crown) to the tip of the stem (not to the tip of the highest leaf blade). Straighten the stem for an accurate measure of its length. The longest stem may not be the most mature stem. Make sure you measure the longest stem, not an average length stem. Step 3: Based on the most mature stem and length of the longest stem, use the side of the stick corresponding to the most mature stem and read the NDF from the tallest plant from the standing alfalfa forage. Then repeat these steps in four or five representative areas across the field. Take a few more samples for fields larger than 30 acres. Average all estimates for a field average. How accurate are these methods? In 2000, several
Michigan State University extension agents and specialists conducted
a field stuffy comparing GDD's PEAQ sticks, and Scissors clip for
predicting forage quality in the field. The
methods compared included GDD (base 41° F), PEAQ, and scissors cut.
Kathy Lee summarized the project and reported on it at the 2002
tri-state dairy conference in Indiana. The project consisted of samples and data collected from alfalfa fields in 35 locations throughout Michigan, including five locations in the Upper Peninsula. Daily maximum and minimum temperatures were collected with electronic data loggers at each field. We compared the NDF predicted from these samples with the NDF of chopped alfalfa both before and after ensiling in laboratory silos. Immediately prior to cutting the alfalfa field, the PEAQ stick was used to predict NDF and the scissors-cut sample was taken. The field-wilted alfalfa was sampled immediately prior to chopping. This sample was manually "chopped", and either dried within 24 hours or immediately ensiled in laboratory silos. The scissors-cut, chopped, and ensiled samples were analyzed for NDF concentrations by wet chemistry procedures at the Michigan State University, Department of Animal Science. NDF concentrations of ensiled alfalfa samples were predicted adequately by all three methods for first and second cutting. Although there was little difference between GDD and PEAQ for first and second cutting alfalfa, we do not recommend using GDD for predicting NDF concentration of second cutting alfalfa due to the potential of inadequate soil moisture during second cutting growth. The results are as follows: §
The scissors-cut method was the only method
that adequately predicted NDF for third cutting. §
The error associated with the methods was
slightly lower for PEAQ compared with GDD and scissors cut for first
and second cutting. When PEAQ was used to predict NDF, about two-thirds
of the samples were predicted within +2.3 units of NDF for
first cutting and within +2.8 units of NDF for second cutting.
When GDD was used, about two-thirds of the samples were predicted
within +2.6 units of NDF for first cutting and within +3.1
units for second cutting. § There was good agreement between NDF concentrations of the fresh chopped and ensiled samples harvested from the same fields at the same time. Please note, though, that these samples were handled under ideal conditions. It is likely you would see greater differences in NDF between fresh and ensiled samples with standard ensiling procedures on the farm. Based on the results of this project
and previous research, we recommend the following: § Begin cutting alfalfa at 40 percent NDF (750 GDD, base 41°F) for upright silos and 38 percent NDF (680 GDD, base 41° F) for horizontal silos. Start even earlier for horizontal silos if it takes more than a week to finish harvesting. § The GDD and PEAQ methods cannot be used for fields containing grass. § Fields containing grass should be harvested first. Start with the fields with the most grass first and finish with the purest alfalfa fields. We know that grasses need to be harvested when they reach the early boot stage of growth for best quality. When grasses head out, the NDF content increases rapidly resulting in much lower quality. How much earlier a grass/alfalfa field should be harvested is a judgment call by the producer. We do not have estimates for NDF percentage for grasses at different stages of growth. § Consider using the scissors-cut method for fields containing grass and for third cutting alfalfa. Shipping samples to the forage testing laboratory by next-day delivery will help to minimize deterioration in sample quality. Wet chemistry analysis is most appropriate for scissors-cut samples. These prediction methods should not be used to replace feed testing to balance rations. The methods are used to help farmers make decisions on when to begin harvesting their fields to meet their forage quality goals. Even though these methods are better than using the calendar date, we are still dependent upon good weather for harvesting. Let's all hope for a successful season to meet forage quality goals. For more information on localized growing degree day numbers visit: |
Regional reports |
2 - Southwest |
Weather Commodity reports The following is a compilation of GDD41 recorded in the southwest region as of May 11.
Other area GDD41 Accumulations can be found at the following website: http://www.agweather.geo.msu.edu/Ldm-Data/bs41.dat The wheat crop has progressed quickly with the warm temperatures and ample moisture. Wheat growth stage is variable with the temperatures in any given location, but the most advanced wheat is just pushing beyond the boot stage in the southernmost areas. It is time to keep an eye on the leaves for fungal pathogens. Powdery mildew has been seen lower in the canopy on several fields, but has not progressed towards the upper leaves at this point in the fields that I have seen. We want to protect the flag leaf from fungal pathogens because it provides the majority of the photosynthate for the development of grain. Be prepared to begin scouting fields now for the development of fungal pathogens on the upper leaves. Commercial corn planting is nearing completion in many parts of the region. Early-planted corn is up and is beginning to green up nicely. Growers have been struggling to get pre-emergence spray programs on the fields with the wet weather. Some areas of fields, especially in southern Kalamazoo County, have been struggling with drainage issues. Plants seemed to have survived the localized flooding to this point. We may have to be prepared to dust off the rotary hoe if crusting conditions develop on fields not yet emerged. Nitrogen losses through leaching and de-nitrification will most likely be an issue in areas where the N was applied pre-plant that received 3 to 5 inches of rainfall or more during the last week. This may be a good year to consider PSNT to evaluate soil nitrogen levels late in the season. Perhaps the biggest challenge for seed corn right now is that wet soils are delaying the planting of companion male or female rows that have already been planted. While there is plenty of time left in the growing season for the crop to develop, timing of planting to allow for proper pollination can be critical. Some seed corn is being planted in wet conditions to help make sure that the "nick" is correct. Snow cover last winter may have provided enough insulation to allow volunteer potatoes to be an issue this season. Early planted potatoes are beginning to emerge. Plants look good at this point. Soybean planting has been lagging behind schedule due to the wet conditions. We have several fields that have emerged in St. Joseph County. We will have to watch for the development of crusting conditions as the soils begin to dry out in planted fields pounded with heavy rains. Rotary hoeing can help to break up crusts, but you should avoid this operation if the plants are in the crook stage of development (just prior to emergence) because excessive stand losses can result. I did not see any sign of cutworm clipping on the few fields that I looked at on Wednesday. |
3 - West Central |
Weather Commodity reports Grasses are somewhat taller than alfalfa.
Orchardgrass will be maturing
sooner than we would like. Pastures are growing rapidly Wheat is in growth stage Feeke's 8-9. Most fields look
good with some powdery mildew low in the canopy on susceptible varieties. Oats are 95 percent planted with most of the crop emerged
and growing well. Corn planting is holding at 30-40 percent of the crop planted. Corn is emerging. Fields will need to be monitored and
flood damage accessed. |
Weather news |
A meandering frontal boundary draped across the Great Lakes Region has resulted in widespread showers and thunderstorms on almost a daily basis in Michigan since last Friday (May 7). Rainfall totals for the four-day period between May 7-10 ranged from less than 0.25 inches in the Upper Peninsula to more than 5 inches in sections of the central and southern Lower Peninsula where localized flooding was reported. While it led to major delays in spring planting and other fieldwork, the rain also significantly reduced or eliminated long-term precipitation deficits in many areas. |