Agronomy Update - Emergence Concerns for Recently Planted Corn
May 23, 2018
Agronomy Update - Emergence Concerns for Recently Planted Corn
While walking fields and plots, as well as discussions with a few growers, I am seeing more crusting and emergence issues. A couple common denominators (My math teacher was right I am using denominators) are:
- Planting in less than ideal conditions, wet or following the field cultivator to close and not letting it dry
- High Clay based soils that retain water and do not heat up very fast
- Slow Germinating Hybrids, every company has some, however some companies have more than others
- No liquid starter, zinc or Ascend. These products assist with emergence.
It appears the biggest concern we have so far is with seed that was planted May 5-11 (for those of you like me that lose track of time that is the week prior to Mother’s Day May 13th).
In reviewing Growing Degree Units (GDU’s) by planting dates we are about 100-170 GDU’s for corn that was planted May 5-11th.
|
Planting Date |
GDU'S |
Growth Stage |
|
28-Apr |
240.5 |
V2 Collar on second Leaf |
|
5-May |
172 |
V1 First collar on emerged leaf |
|
11-May |
103.5 |
Emergence |
In most instances crusting that is 3/4 of an inch or less can be mediated by a gentle rain that mellows the crust and allows the coleoptile to push through. A crust that is thicker may not allow the plant to push through. At this point a rotary hoe or other implement needs to break this crust to allow plants to get through. The decision to do this needs to be tempered with the fact that you will have some mortality on plants that have already emerged or just starting to emerge.
If a corn stand is 22-24,000 plants or less I am more likely to replant. At 22-24,000 plants it tends to be a grey area as what to do, I tend to lean more on keeping the stand deciding if additional tillage such as a rotary hoe would be of a benefit.
The take home statement is, you need to scout fields that were recently planted to see if that crop is emerged, or if corrective actions need to take place to save the stand or lastly, if it needs to be replanted.
If you have questions on this or other Agronomic concerns, please contact your local Central Farm Service Agronomist or myself.