Back

On May 23, 2018

To Monitor Planting Depth in Corn and Soybeans  

With the warm weather finally upon us, many planters will be in the fields this week. While it’s tempting to sink the planter into the ground and get as much done as possible, taking time to make small adjustments to your planter will pay big dividends at harvest time.

Extension Agronomist Dwane Miller reminds us while in the field, you should pay attention to seeding depth. While it may not one of your favorite jobs, getting off the tractor seat and digging for seeds is a task that everyone needs to do. Planting at the improper depth can result in less than ideal stands in certain situations.

As a general rule, planting corn at a depth of 1.5 to 2.5 inches is a good target range depending on soil conditions. In our survey of planting depth in the PA Five Acre Corn Club last year, 74% of the growers chose 2 inches as their target seeding depth. You need two things to be successful in germinating corn; warm temperatures and moist soil. Take these two factors into consideration when making your planting decisions. Plant corn on the shallower side of this desired range when soils are colder and/or soil is moist, and on the deeper side when soils are warm/dry. Also, plant on the shallow side of the range if you are in heavy soils, or you anticipate crusting to be an issue.

Compared to other grain crops, soybeans require more water for germination. In order for soybeans to germinate, they must take in 50% of its weight in moisture. Therefore, planting into moist soil with is ideal. Good seed to soil contact is also important to allow soybean seed to allow water movement into the seeds. Soybeans are planted at a more shallow depth compared to corn. Ideally target planting at a depth of 1”-1.25” in optimal soil moisture conditions. Planting too deep will result in poor emergence in the field. Michigan State University agronomists suggest that we should target our depth so that the soybean seed is placed into at least 0.5” of moist soil.

While you’re off the tractor, be sure to also check to insure that your seed trench is closed and that you are getting good seed to soil contact. This is especially important for no-tillers. We may be tempted to get into the fields when they are a little too wet, and this could create an opportunity for poor germination and reduced stands. Also worn planter or drill parts can cause hair pinning which reduces seed to soil contact and ultimately emergence.

To Understand Factors Impacting Burndown Herbicides

 

Air temperature before, during, and after application can influence control with burndown herbicides. Cold nights (<40°F) will reduce activity, particularly for glyphosate, and especially when followed by cool (<55°F) cloudy days. Wait 2 or 3 days if possible after the nights have warmed before making foliar-applied applications. Extension Agronomist Dwight Ligenfelter provides these reminders to consider for common foliar-applied burndown products.

 

With Glyphosate remember to use a sufficient rate, which generally ranges from 0.75 lb ae to 1.5 lb ae/acre. The 22 fl. oz rate of Roundup, 24 fl. oz Durango or Touchdown Total or 32 fl. oz rate of Credit, Gly Star, Makaze, Rascal, etc. = 0.75 lb. In general, application alone along with appropriate adjuvants (surfactant + AMS) is best and reducing the carrier volume to 10 gal/acre can increase activity. The AMS or another water softener helps alleviate hard water problems and also can reduce antagonism if tank-mixing with other herbicides such as 2,4-D. Be sure to add the AMS first to the spray tank and agitate before adding the glyphosate. Do not add 28 or 32% UAN or other fluid fertilizers to the spray tank. If the water source has a high pH (8 or greater), consider adding an acidifying agent to the spray solution. Avoid tank mixing with higher-rate (> 0.25 lb) clay-based herbicides (WDG, WG, DF, DG, F) like atrazine, simazine, and metribuzin. Other herbicides such as 2,4-D, dicamba, clopyralid, Balance or Corvus, Resolve or Basis Blend, etc. are OK. Use a clean water source that does not contain soil or other sediment that can reduce glyphosate activity.

 

Gramoxone SL contains paraquat and is applied at 2-4 pt per acre for control of emerged weeds. Paraquat is the main alternative to glyphosate for nonselective burndown. Since it is a contact herbicide, apply in 20 gallons of liquid carrier or more and do not use flood jet tips for best results. Use flat fan nozzle tips that produce a uniform spray pattern and thorough coverage. Be sure to include an appropriate nonionic surfactant. Add a triazine herbicide (atrazine, metribuzin, etc.) to Gramoxone to increase burndown activity. Using UAN as a partial carrier will also increase the activity. Use a clean water source that does not contain soil or other sediment that can reduce Gramoxone activity.

 

Quote Of The Week: “How far you go in life depends on your being tender with the young, compassionate with the aged, sympathetic with the striving and tolerant of the weak and strong. Because someday in your life you will have been all of these.” George Washington Carver