Insect issues

by | May 4, 2020 | Crop Watch

Most people involved in Ag agree that they have never seen such a fast and problem free planting season. Lots can happen in ten days if most of the days are sunny and rain free. With more 16 to 36 row planters operating these days one does not see that many rigs in the field at one time. With more of them equipped with autosteer, RTK, and high speed attachments they can run more hours and across more acres each day. Thus across a good portion of the state most of the corn and a sizeable % of the soybean acres are planted. The first planted acres were emerging by late last week and could be rowed as of Sunday afternoon. That all occurred with warmer than average temperatures. Now we get to see what happens with the below average temps predicted for the next week or so. That could be enough to make bean planting slow in the more northerly regions of the state. (The one issue seemed to be electrical and computer problems with brand new planters or the tractors pulling them.)

After about a month of schools, churches, restaurants, and offices being closed down it was good to hear and see a portion of these facilities open up again. The average opinion among Ag people was that the people of many years and those that had pre-existing health challenges needed to stay behind closed doors, but for the economy and society to function the people who have stuff to get done and jobs to finish just wanted to be left to do their thing. Getting scared because some windbag on TV or radio personality was making overstated claims did not make it gospel. The boogey man of their youth did not get them and this one was not going to either.

I have had more people tell me they did enjoy reading and listening to the news and interview of Judy Mikovitz, Rashid Buttar, and Dr. Shiva. It strengthened their view points and provided arguing points.

The Planting Seasons

Based on what we saw in the years following delayed planting seasons we were expecting corn and bean farmers to go full speed ahead once it warmed up and the ground was fit. The only risk it seemed was whether they should plant on the Sunday or Monday when the night time temps were expected to do down to near freezing. Then on Tuesday even the cautious ones began to run full bore. The tasks at hand later in the week were to get the last bean fields planted or to apply the post emerge products in time to catch a shower to incorporate the herbicides. On both Saturday and Sunday, the rain clouds that were moving into the state from Nebraska and S Dakota looked promising on the radar screen but never materialized and made it to the rain gauge. Thus now we could use a rain of .5 to 1” to help germinate any shallow seeds and to activate the weed control products.

Insect Issues

It is always good to try to read nature and the weather signals as to how they affect insects that view your crops as a food source. There are a few things to be aware of:

1. It was a milder than normal winter season with fewer hours of temps below 10 or 20 degree F. This is expected to contribute to higher than normal survival rate of bean leaf beetles. They seek in the fall in tall grass prairie and under brush and tree residue. In a normal planting year earlier than normal planted field in a neighborhood would be highly attractive to the hungry beetles. This year there are many such fields, so no individual field should stand out to any army of hungry feeders.

2. The strong winds from the South and SW two weeks ago blew in winged pests on several of those days. The insect trap catches by the UNL entomologists included saw many black cutworm moths in mid to late April. The fields likely to be targeted for egg laying by the moths will be those filled with lush growth of winter annuals. Looks for the leaf and stalk feeding in such no-till or conventional tilled fields after 200 GDUs accumulate. Take action if the treatment threshold levels are reached or approached.

3. I mentioned in recent weeks about a Cornell extension entomologist who has been working 30+ years to introduce wild strains of persistent nematodes that eat corn CRW larvae. This lowers the risk to second year fields being damaged by CRW feeding on the roots. There is a chance that there will be plots where his select strains will be released in 2020. Having been in a few fields where SS hybrids were planted following 2018 soybeans were 50% flat at last year’s harvest, Elson believes this will give us another tool to use in the arsenal available to us. No one tool has proven to last forever. I can comment more on this later.

This would give him three areas where his little worms are being tested. In upper NY state. Down near Dalhart, TX. Now a third in the #1 corn state. If they can tolerate the extreme in conditions in both of those areas living in IA should be very tolerable. These are priced at about $50 per acre and are applied the year before they are expected to give control. He also wants them paired with another method of control.

You will enjoy these two informative articles on rootworms:

Invasion of the Rootworm Snatchers

Biological Control of Corn Rootworm with Persistent Entomopathogenic Nematodes

Spring or Early Season N Tests

Applying the exactly accurate amount of N to each field is the dream of corn farmers as well as EPA and DNR regulators. Tactics that have been used as strategies include taking soil cores in each field during the early growing season and having them analyzed for N content. Such tests are good at taking snapshots in that instant. In years where the springs and early growing seasons have been dry those sampling results can indicate how much N has been stored in the top 30” and would be available for plant root uptake.

Before the Solum soil testing lab in Ames was shut down they were developing a new N test that would detect all available forms of N that could be measured with one run thru the lab. Now that more farmers having Y-drop equipment available to them and the fact that stabilized urea can be applied with tall tired dry spinner spreaders, there is now equipment that can be used when supplemental N is needed.

Three companies that have biologicals capable of fixing atmospheric N into the plant or soil have been selling their products into the farmers’ hands this season. Azotics with their Gleucono acetobacter ‘Envita’showed promise in limited trials last season. The Blooming Blossom Company has their Azotobacter strains that also fix atmospheric N when applied foliar along with a food source. Pivot Bio is also marketing a bacterial product this spring. Other companies have included the two Azotobacters in their mixes for years. A drier year may allow for more accurate results than those produced in 2019.

Application Time

No-till operators are the growers most cognizant of the challenges they face in eliminating early germinating and emerging weeds. They don’t have the option of using steel to take out the weeds like Marestail, Giant Ragweed or Kochia that have become problems in areas. Since the seeds germinate based on degree days and the side slope soils can warm earlier in the season these areas can hold more of these problem weeds and need a burndown product included with any residual mix being applied.

Redox Chemical Company

We got alerted to this company back in 2017 and visited their research location in Idaho later that season. We had heard good things about their main product which was calcium silicate or Mainstay Si. Based on third party literature and what I had picked up from seasoned veterans from across the country the results they were seeing as to increasing the stalk strength, stress tolerance, and insect/disease tolerance of plants were all real. Other attributes imparted by the Mainstay Si were thicker leaves that captured more sunlight energy, increased mineral uptake, and longer shelf life for specialty crops.

They are one of the few Ag companies that mentions the reduction of oxidative stress by the use of their materials and how it leaves the plants more productive as a result. As a result there are more products from Redox being placed into trials to see which of their other products would beneficial to Midwest growers. This knowledge base and attention paid to manufacturing exactness is why they are the only U.S. plant nutrition firm with ISO 9000 certification.

Bob Streit is an independent crop consultant and columnist for Farm News. He can be reached at (515) 709-0143 or www.CentralIowaAg.com.