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Showing posts with the label management

ISAP | Conservation Practices, the Supply Chain, & Consumers

Margaret Henry, Director of Sustainable Agriculture - Pepsico
Ryan Sirolli, Global Row Crop Sustainability Director - Cargill

Companies along the food and fiber supply chain are thinking through how to incentivize clean water and conservation practices while providing for consumers’ wants and demands.
 

Projected Cutting Dates for Black Cutworm in Corn



Farmers should be on the lookout for black cutworm in their corn fields.

The earliest projected cutting dates were late last week in Montgomery County. University of Illinois Extension Entomologist Nick Seiter says fields especially at risk to having plants cut by the black cut worm include those with later planted corn and those sown into grassy weeds or a late terminated cover crop. Seiter explains, “What you are going to want to do is to scout your field. Look for plants lying on the ground that appear to have been cut with scissors. This is different looking than damage from a bird digging up the plant looking for the seed. These corn plants will be cut off. When you start finding that, scrape around in the residue looking for the larvae. The black cut worm larva is dark colored, with a greasy appearance. It is not slimy, but it looks like it has been coated with Crisco. If you find the worms and about three percent of the plants have been cut throughout the field it is the time to initiate a treatment.”

Seiter says there are several pyrethroid insecticides that can be successfully used as a rescue treatment. He offers these black cutworm management pain on the University of Illinois the Bulletin website.
  • Infestations are more likely in later planted corn, as delayed planting means larger cutworm larvae are present at earlier stages of corn development.
  • Black cutworm moths prefer to lay their eggs on grasses, not bare ground. Therefore, fields with grassy weeds present at or shortly before planting are more likely to experience damaging populations. Similarly, monitor fields closely if a grass cover crop (e.g., cereal rye) is terminated while corn is susceptible to cutworm damage (emergence to ~V5).
  • The economic threshold for black cutworm is 3% of plants cut with black cutworms still present in the field. Look for plants that look like they have been cut roughly with scissors close to the base; plants with intact roots were most likely dug up by birds and do not represent cutworm damage. Remember, larvae do their feeding at night and hide in residue or just below the soil surface during the day, so you will have to do a little bit of digging near the base of the plant to find them.
  • Several Bt corn trait packages offer suppression of black cutworm, but these might be less effective under heavy infestations or against later stage larvae. Most pyrethroid insecticides labeled for use in corn will do an excellent job of controlling larvae as a rescue treatment; just remember that they only pay off when an economic threshold has been reached.
Kelly Estes at the Illinois Natural History Survey coordinates an insect trapping network throughout the state and those results, including the black cut worm cutting dates, are posted online at The Bulletin website - that’s bulletin.ipm.illinois.edu and on twitter using the handles @ILPestBulletin or @ILPestSurvey.

Dry Cows | 10 Steps for a Successful Transition Period

Nutrition and management of the dry dairy cow has been an area of extensive research over the last 25 years. Although nutritional requirements during this phase are fairly simple, the sudden transition from non-lactating to lactating state – as well as the physiologic and metabolic processes associated with it – make the transition period a fascinating and important stage of the production cycle of the dairy cow.

read more from the Dairy Focus Newsletter

read more from the Dairy Focus Newsletter

What Is Up with Soybean Yields

read farmdocDaily arcticle
by Scott Irwin, Agricultural Economist - University of Illinois

Soybean yields in the U.S. have been very high the last four years. The U.S. average yield set new records in a stair-step fashion each year between 2014 and 2016. The 2016 yield reached the remarkable level of 52.1 bushels. While not a record, the 2017 yield (based on the November 1 USDA estimate) was 49.5 bushels, the second largest ever. On top of the high U.S. average yields are the numerous reports of field-level yields in the 70s, 80s, and even a few in the 90s.





The high soybean yields of recent years have sparked a debate about what is driving the exceptional yields. In thinking about this debate it is important to understand that there are only three possible sources of soybean yield gain. The first is weather during the growing season. The second is genetic improvement in soybean varieties. The third is a management, which encompasses all aspects of the soybean production process. Genetic improvement and management sometimes go hand-in-hand so that one requires the other.

It is a not an easy task to disentangle the complex and sometimes interacting impacts of weather, genetics, and management on soybean yields. One approach is to use a crop weather regression model to estimate the separate impacts of weather and technology on soybean yield, where technology is the combined impact of genetic improvement and management. I estimated this type of model for U.S. average soybean yields over 1970–2017. A linear time trend was used to represent technological change and summer precipitation and temperature variables were used to represent growing season weather. The modeling results showed that U.S. average soybean yields in 2014, 2015, and 2017 could be explained by a continuation of the linear improvement in technology and good growing season weather. The exception was 2016, when yield was substantially higher than what could be predicted based on a linear technology trend and good weather. It is not clear from this exercise whether we should view the 2016 yield like a 100-year flood or a permanent jump in soybean yield potential.

Agronomic data can be helpful in further disentangling genetic improvement from other sources of soybean yield gain. One recent study collected seed for over 150 soybean varieties released from the 1920s through the 2000s. Using randomized trials from across the country in 2010 and 2011, the study estimated “pure” genetic improvement in soybean yields. The results indicated a linear progression of soybean genetic yield gain from 1970 through 2008. This indicates that the historical pattern of soybean genetic gains in yield have been steady and marked jumps in the rate of improvement are rare. Soybean variety test results from the Department of Crop Sciences at the
University of Illinois provide relevant data through 2017. The yield of conventional soybean varieties relative to the older Williams variety shows no change of trend in recent years. Overall, there is little evidence to date that soybean genetics have been improving at a faster rate in recent years.

If we dig into the soybean yield data for the U.S. state-by-state an interesting pattern emerges that points to important changes in management practices. In general, soybean trend yields in the Southeastern U.S. have been growing at a much faster rate than in other growing regions. This non-linear trend appears to be related to a number of management practices, which can be roughly described as having the purpose of replicating Midwestern growing conditions. This includes planting much earlier in the past, planting earlier maturing indeterminate varieties, including corn in the crop rotation to increase organic matter in the soil, and using raised bed production systems. These management practices have allowed soybean yields in the Southeast to largely catch up with those in the rest of the country.

In sum, the data indicate that the biggest factor explaining high soybean yields in recent years is simply exceptionally good growing season weather. Improved management practices, particular in the Southeastern U.S., have also certainly contributed. A jump in the rate of genetic improvement in soybeans was not likely a big contributor to the surge in soybean yields.