Crop Growth & Development

Key points 

  • Tassel emergence marks the critical shift to reproductive growth in corn, impacting yield.
  • Corn is highly vulnerable to stress during tassel emergence.
  • Selecting disease-resistant hybrids provides additional layer of protection.

The emergence of corn tassels is a pivotal moment in the life cycle of the corn plant. AgriGold Agronomist Chris Ouzts says supporting this key growth phase can significantly enhance yield potential and crop success. 

“The appearance of the tassel signifies a major change as plants switch gears from vegetative to reproductive,” Ouzts says. “It’s basically the halfway point in the plant’s life cycle — and it’s where all the moisture and fertility inputs pay off.” 

During tassel and early reproductive stages, corn is highly susceptible to stress. “VT/R1 is when the corn is most vulnerable to adverse weather conditions. Leaves produce energy for ear and kernel development, and if leaves are injured then yield is compromised.” 

High temperatures are a main concern and can significantly impact pollination. “Heat increases transpiration rates, which when coupled with drought conditions can cause pollination problems and impact silk health. When temperatures get above 95 degrees, you start to see pollen viability reduce and silks can die off due to desiccation.” 

Achieving optimal corn yield requires a strategic approach to supporting tassel development, which Ouzts says includes mitigating stress through moisture and fertility management. 

Water supply and moisture management  

Increased transpiration rates from higher temperatures cause stress and create a moisture deficit. “Corn uses water to cool itself through transpiration — like air conditioning in your house. Corn transpires around .25 to .5 inch of water a day, which could easily be higher during grain fill.” 

To mitigate stress, maintaining adequate water supply and soil moisture is vital. “Don’t let your crop run out of moisture if you can help it — you need adequate water for nutrient uptake and to help keep the plant cool.” 

Fertility and nutrient considerations 

To ensure corn has the nutrients it needs for optimal tassel development, Ouzts says soil testing and timely fertility management are essential. 

“Get soil tested to see what your needs are and have all fertility out by 1,200 Growing Degree Units (GDU) for dryland and 1,400 GDU’s for irrigated corn. That way the plant has everything it needs regarding fertility.” 

Scouting for signs of tassel stress 

Regular field scouting helps identify and address issues early. Ouzts suggests scouting corn weekly from emergence to the black layer. “Look for insect damage, disease, soil moisture conditions and fertility problems — anything that’s going to impact yield — so you can intervene early.” 

Hybrid selection 

Selecting hybrids with strong disease tolerance/resistance and including fungicides in management plans, when necessary, can provide an additional layer of protection against yield-limiting factors. 

“One good defense is to select a hybrid that has a solid disease package,” Ouzts says. “If you know you’re going to have a problem with whatever disease or the hybrid you plant is not as strong on a certain disease, then include a fungicide in your management plans.” 

The development of corn tassels is a pivotal moment in the life cycle of the corn plant. Understanding the dynamics of this stage and implementing effective stress mitigation and fertility management strategies can significantly enhance yield potential. 

For more support navigating this season’s challenges, reach out to your local AgriGold agronomist.