The enrollment deadline for the optional Average Crop Revenue Election (ACRE) program is fast approaching. The Pennyroyal Farm Analysis Group and the University of Kentucky have released a newsletter updating producers on how the optional ACRE program works and the 09 wheat situation relationship with ACRE. You can view the newsletter at: http://www.ca.uky.edu/agecon/index.php?p=110 and clicking on "ACRE Program, Pennyroyal Farm Analysis Group and UK"

Yellow Soybeans and Soil Compaction

Image 1: Yellow soybeans in this field are the result of sidewall compaction.

The spring rush of planting is catching up to the soybean crop in some fields. Surface compaction and sidewall compaction was most likely caused by planting when fields were a little too wet. The compacted soil has restricted root growth on soybeans. Until now, there has been enough water to keep most nutrients within the root zone and the soybeans looked fine. As the soybeans reach full pod development (R4) the plants are rapidly accumulating nitrogen and potassium. The restricted roots are not taking up enough nutrients to sustain plant growth. Plants turn yellow.

Planting all fields in perfect conditions is impossible most springs and especially this one. Timely rainfall now will help move nutrients into the root zone. Yield losses from compaction could be very minor or very sever, depending on rainfall, soil fertility within the root zone and severity of compaction.

Fertilizers at this point will likely have little impact on yields. The soil scientists will address this in more detail.

As more soybeans across Kentucky get closer to full pod and beginning seed development, I expect we will see more yellow soybeans.

Image 2: Soybean roots restricted by sidewall compaction. Root growth is limited mostly to the furrow created during planting.

Image 3: Soybean roots restricted by compaction just beneath the soil surface. Root growth is bending to curve around the compaction. The overall root mass is reduced from the compaction.

Image 4: Soybean roots with little to no restriction. The whole plants are greener and larger. Root mass is greater and there are more nodules per plant.

Image 5: Yellow soybeans have roots with restricted growth while the greener soybeans have little to no restriction on root growth.

Soybean Aphid: Numbers are on the rise in Central Kentucky… At least a little!

Over the previous week we have seen an increase in the number of locations reporting the presence of soybean aphid (SA), and in one case a substantial increase in the number of reported aphids per plant. Neither of these finds is unexpected, nor do they indicate an immediate problem but they do illustrate that pest numbers are increasing slowly.

This is typical for SA in Kentucky. Experience has shown me that when soybean aphid populations are detected they will most likely be found in the counties between I-65 and I-75. Also, this area generally has larger populations than found in the western production area. In addition the only SA populations that have approached threshold levels have occurred in these counties. Nevertheless, we do know that this pest is active state wide so no one should dismiss it out of hand.

Our history with this insect tells us that we are unlikely to need a treatment but insects are very adaptive, and local populations can vary from the norm. Keep an eye on them!

See Kentucky Pest News at: http://www.uky.edu/Ag/kpn/kpnhome.htm for the complete story.

Worrying about Small Soybeans

Some farmers are concerned that the smaller growth of soybeans could result in reduced yields. Some are questioning the use of foliar fertilizers and/or fungicides to help make up the difference.

Soybeans were planted late across most of the state. According to the latest Crop and Weather Report from NASS, soybean flowering is at 35%, behind the five-year average of 47%. Most farmers' "internal clock" says that soybeans should be larger by now. Most years, that is correct. This is not most years.

Some soybeans are getting to flowering (growth stage R1) and may be a little smaller than in previous years. The cooler temperatures combined with later planting dates will cause smaller plants. The smaller plants could be a concern if rows are not closed in shortly after flowering. If the soybean rows are closed, then height is less of an issue. As long as the rows are closed, tall plants do not automatically equal high soybean yields.

If the rows are not closed and the soybeans begin to flower, then yield potential is likely lost. As the soybeans move into pod development and the rows are not closed, yield potential is likely lost. If the soybeans get to seed fill and the rows are not closed, yield potential is lost. This brings us to the main question: will a foliar fertilizer or a foliar fungicide help? The short answer...probably not.

Fungicides will not improve the speed at which soybeans grow and will not help with canopy closure, in the absence of a disease. Fungicides will help soybeans retain leaves, if a disease is present in the field. However, the cooler night temperatures and the smaller soybean plants both contribute to less of a threat from diseases this season.

Foliar fertilizers will not compensate for lower temperatures. They will not increase the speed of growth, assuming P2O5 and K2O levels are adequate in the field. They will make the plants greener and that might make someone feel better.

If your, or your neighbor, is absolutely set on spraying something, then consider the foliar fertilizer. It will likely make the plants greener and it should cost a little less than the fungicide. Or, take that money you would have spent on the foliar product(s) and take a trip someplace warm. Someplace where you don't have to see the soybeans for a couple weeks. It just might make everyone happier, including your friends! For others, keeping that money in the bank may be the best stress reliever right now.

Bottom Line:
Small soybeans or late-planted soybeans that do not reach full canopy by flowering probably have lost some yield potential. Cooler temperatures also reduce the chances of soybeans reaching full canopy by flowering. In hindsight, the best management practice would have been to plant in 7.5-inch rows. The narrow rows would have improved the chances of getting complete canopy closure by flowering. Foliar fertilizers and fungicides will not make up the difference in temperatures, planting date or row spacing.

New Wheat Publications

The Small Grains Variety Trials for 2009 is available at: http://www.ca.uky.edu/agc/pubs/pr/pr586/pr586.pdf

The Wheat Guide (ID-125) has been completely updated with new content, photos and format and is available at: http://www.ca.uky.edu/agc/pubs/id/id125/id125.htm

The Kentucky Small Grain Growers sponsored the updated version and is partly funding the printing of copies.

Printed copies of both publications should be available within several weeks. Both of these publications are linked to the Grain Crops Extension Website at: http://www.uky.edu/Ag/GrainCrops/

Current Status of Soybean Rust

The current soybean rust distribution in the US has changed very little in the last month. Currently, the disease is found in a very small number of soybean sentinel plots in Florida, Louisiana, and Alabama. It is also found on kudzu in those states plus Georgia and Texas. The main difference between the present SBR distribution compared to the same date a year ago is the presence of SBR in Georgia, greater activity in Alabama and Louisiana, and less activity in Florida. There has been little spread of the disease in recent weeks, presumably due to hot, mostly dry weather. So for now, the soybean rust risk for Kentucky continues to be very low. This status could change quickly, so I encourage you not to let your guard down. Hopefully, this will be another dud year for SBR.

First Soybean Aphid for 2009 Collected

The first soybean aphid (presumed) for the 2009 season in Kentucky has been collected. A singe juvenile aphid was found on a leaflet from our “100 leaf” sample from the Henderson Co. sentinel site. Not much of a find perhaps, but it does let us know that the Soybean aphid is in Kentucky. The aphid is presumed to be a soybean aphid because only a single very young juvenile was collected and these cannot be identified with complete surety . The aphid has been isolate on a soybean plant in the lab. If it forms a colony or lives to an age that can be identified then, we will know for sure the correct identification. But given the location of the collection and the look of the aphid it is very likely soybean aphid. At this time there are still no reports of soybean aphid in Kentucky suction traps, in whole plant samples from sentinel plots, nor reports from consultants or producers. It is still early in the season for Kentucky. We have many early stage beans that will continue to grow right up until frost. Continue to scout regularly for this and other soybean pests. Posted by Cory Walters for Doug Johnson.

How ACRE will Calculate the Average State Yield Per Planted Acre.

I had a question on how the ACRE program will calculate the average yield per planted acre for Kentucky. The ACRE program will use yields provided by the National Agricultural Statistics Service (NASS). However, the calculation for yield per planted acre used by the Farm Service Agency (FSA) will be a little different than how NASS defines yield per planted acre. The FSA defined yield per planted acre as harvested acres plus failed acres. Failed acres are intended for harvest but not harvested. To then calculate yield, divide the state’s production by the harvested acres plus failed acres. With few failed acres in Kentucky this approach will not make much of a difference but a difference may be seen in the FSA calculated yield per planted acre and the published NASS yield per planted acre. The FSA yield per planted data will use come from both published and unpublished NASS data. You can reach Cory Walters at cgwalters@uky.edu