Skip to Main Content

Impact of Agronomic Management Practices on Silage

Categories: PLANTING, CORN
Share:

Planting and Growing Considerations

Seeding Rate

Line graph of seeding rate influence on silage quality and yield.
Graph 1.

Seeding rates are routinely adjusted for corn produced for grain to optimize yield potential. Increasing grain yield with higher seeding rates also increases overall silage tonnage up to a point, but simultaneously reduces quality. The increased plant biomass from additional plants tends to dilute starch contributed from grain, resulting in higher fiber levels. As a result, milk per acre of silage can be increased with higher seeding rates, but milk per ton will decrease (Graph 1). Increasing seeding rates 2,000 to 4,000 over normal corn grain seeding rates will typically maximize both yield and quality.

Planting Date

Planting date has minimal impact on silage yield unless delayed into late May or June. It is common to see tonnage loss of 1 ton per week if planting after the last week in May, however, reasonable yield can still be achieved with June plantings. Energy levels are likely to reduce in later planted silage as a result of lower starch levels from reduced grain fill.

2 Ways Fungicides Improve Silage

Bar graph of the response to the R1 application of Miravis Neo Fungicide in corn silage.
Graph 2.

Managing disease in silage corn can be just as important as it is in grain. Previous research has illustrated how fungicides can improve silage yield potential and quality before harvest and during the ensiling process (Graph 2).

  1. Pre-Harvest Benefits
    Fungicide applications can prevent fungal diseases in the field, which can preserve leaf area to improve tonnage and possibly reduce the number of fungal pathogens ensiled with corn. Fungal diseases have also been known to cause a plant defense mechanism in which cell walls increase lignin content after being infected by pathogens, resulting in lower silage quality. Fungicide applications have shown the ability to minimize this lignin increase and improve silage quality with neutral detergent fiber (NDF) reductions and increased neutral detergent fiber digestibility (NDFd) and starch content.

  2. Ensiling Benefits
    Previous research has shown increased levels of lactic acid during the ensiling process when corn received foliar fungicide applications. Lactic acid is important for lowering pH levels to preserve silage for feeding later. Reducing fungal pathogens with foliar fungicides likely increased the lactic acid content and the fermentative quality of corn silage.

Harvest Adjustments

Harvest Timing and Moisture Content

Bar graph comparing three hybrid harvest moisture differences in relation to milkline.
Graph 3.

One of the most important management factors is aligning harvest timing to maximize nutrient value and deliver silage moistures that best fit the storage type. Ensiling at moisture higher than the target will cause poor fermentation and nutrient loss, whereas too dry of silage will pack poorly, causing mold and spoilage. Recommended moisture contents are 65-70% for horizontal silos, 63-68% for conventional tower silos, 55-60% for limited-oxygen silos and 65% for silo bags. Milkline is often referenced for targeting correct harvest moisture. However, weather and hybrid variations make this a poor indicator, as illustrated in the graph comparing 3 hybrids with different kernel drying characteristics (Graph 3). Forage moisture testers or microwave ovens can be used to determine harvest moisture quickly. If testing shows moisture is above ideal, use the dry down rate of 0.5-0.75% moisture drop per day to estimate the best chopping dates.

Cutting Height

Line graph comparing the influence of cutting height on NDF digestibility, milk/ton, tons/acre, and starch average of two hybrids at 4 site year locations.
Graph 4.

Cutting heights ranging from 2-3” in some areas to 8-10” in other regions are utilized for a variety of reasons, including changing the quality or simply to avoid equipment damage from stones. However, a 6-8” cutting height is most common. Increasing cutting height is a management practice that can increase energy content and NDFd by reducing total stover while maintaining grain content. Previous studies have shown adjusting 6” cutting heights to 18” can increase starch and NDFd levels by 2-3% points (Graph 4). Tonnage reductions are the trade-off for increasing quality. Increasing cutting height may be appealing if hay or haylage in storage is known to have lower fiber digestibility or if you have more acres dedicated to silage than needed.

Chop Length

Longer cut lengths will make it more difficult to achieve a good pack, allowing more space for air between forage particles during the ensiling process which affects the fermentation process. However, shortening the cut length will reduce physical fiber and its effectiveness. Finer chop will improve packing in all silo types and is especially important in upright silos where there is less opportunity to adjust pack methods. The recommendation for the theoretical cut length of unprocessed silage ranges from 3/8” to 3/4” in length and 3/4” for silage processed with 1-2 mm. roller clearance.

Kernel Processor

As kernels begin to mature, a starch-protein matrix forms that make it harder to digest. Kernel processors installed on choppers smash kernels to increase starch digestibility. The value of processing kernels may not be observed with corn in early milkline stages, but typically provides nutritional advantages if harvested when milkline is halfway down the kernel or later stages.

Agronomic Silage Hybrid Selection Characteristics

Relative Maturity (RM)

Planting a hybrid with a RM up to 10 days longer than an adapted full-season grain hybrid can offer yield advantages and typically still reach harvest before fall frost risk in most areas. If fields may be utilized for grain harvest, you may not be able to increase RM as much. RM selection also needs to account for planting date spreads and the capability to harvest fields in a given time.

Root Strength

Hybrid root strength is important to ensure plants are standing well to chop at an efficient speed.

Disease Tolerance

Many silage acres will often be in a continuous corn rotation, resulting in a higher risk of potential disease presence. Hybrid selection and placement should consider tolerance to diseases such as gray leaf spot, northern corn leaf blight and other regionalized diseases such as tar spot. In addition, foliar fungicide applications can also help reduce disease risk in fields.

Insect Trait Selection

Due to ground limitations and feed needs, silage acres often lack crop rotation. Consecutively planting multiple years of corn greatly increases the risk of insect populations and potential damage from insects. Trait selection should consider potential risk of damage from both below- and above-ground insects as well as disease that can supervene insect damage.

Bar graph showing myocotoxin reduction with agrisure viptera trait.
Graph 5.
  • Corn rootworm risk increases with each consecutive year of corn rotations. Agrisure Duracade® traited hybrids and Force® 6.5G insecticide may help mitigate risk.

  • Ear-feeding insects such as western bean cutworm (WBC) and corn earworm can reduce grain and starch in feed rations. Selecting hybrids containing the Agrisure Viptera® trait, the only insect trait registered for WBC, can play an important role in mitigating ear feeding.

  • Mycotoxins can occur for a variety of reasons but are often associated with pathogen infection of grain following insect feeding damage. Ear protection with insect traits can indirectly help reduce the potential risk of silage mycotoxin contamination, as shown in Graph 5.

Stay-green

Hybrids with good late-season health or “stay-green” are known to better maintain green leaf area for a longer period of time. Stay-green can help widen harvest windows and ensure proper plant moisture to minimize poor silage pit packing and spoilage or mold damage associated with it. Utilizing stay-green for expanding the harvest window should not be heavily relied on. Some hybrids will rapidly lose kernel moisture while leaves remain healthy, creating a starch-protein matrix that is harder to digest. Kernel processors can help improve starch digestibility once grain moisture starts to drop.

Stay-green corn silage pile next to a green corn field.
Hybrids with good stay-green can help widen harvest windows and optimize plant moisture for packing. Photo source: Syngenta.

Test Weight

Test weight is a measure of corn grain bulk density that is sometimes associated with kernel texture. Test weight tends to increase as grain becomes drier. Test weight is loosely related to kernel hardness, which is also known to influence livestock feed to gain ratio in feeder cattle. However, as silage is harvested at a higher moisture content, it is not as great of a predictor for silage quality.

multiple cows in a feeding pen in a building eating starch.
Increased starch digestibility is known to improve energy availability for dairy cows. Photo source: Syngenta.

Approaches to Characterizing Hybrid Quality

  1. Fiber Digestibility
    Due to the relatively large amount of silage being in the form of stover, understanding fiber digestibility is very important where corn silage is the largest portion of feed rations. The relative fiber digestibility of a hybrid is largely dependent on how much lignin is present in silage. Lignin is an indigestible fiber that has no energy value to animals and helps compose the total fiber content of forage, expressed as NDF. Corn silage with a low NDF is desirable. NDFd measures the amount of NDF that can be digested, and larger values are more desirable. Hybrids vary significantly in quality due to fiber content and digestibility.

  2. Starch Digestibility
    Increased starch digestibility is known to improve energy availability for dairy cows, thereby improving milk production and/or feed efficiency. Besides hybrid differences, multiple management practices such as harvest timing, kernel processing and length of time in storage can greatly affect starch digestibility. Short-stature hybrids or raising chopping height can quickly reduce stover to grain ratio resulting in higher starch content as well.

  3. Whole-Plant Digestibility
    Total digestible nutrients (TDN) describe the energy content of feed as the sum of the digestibility of different nutrients. TDN is often based on calculations using acid detergent fiber (ADF), which is a low-cost and rapid turnaround method to predict energy content. Significant variations in digestibility of fiber often cause inaccuracies in ADF values and TDN values tend to underpredict forage feeding values.

All photos are either the property of Syngenta or used with permission.

Syngenta hereby disclaims any liability for Third Party websites referenced herein.

Performance assessments are based upon results or analysis of public information, field observations and/or internal Syngenta evaluations.

© 2022 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties. Please check with your local extension service to ensure registration status. AAtrex 4L, AAtrex Nine-O, Acuron, Agri-Flex, Agri-Mek 0.15EC, Agri-Mek SC, Avicta 500FS, Avicta Complete Beans 500, Avicta Complete Corn 250, Avicta Duo Corn, Avicta Duo 250 Corn, Avicta Duo COT202, Avicta Duo Cotton, Besiege, Bicep II Magnum, Bicep II Magnum FC, Bicep Lite II Magnum, Callisto Xtra, Cyclone SL 2.0, Denim, Endigo ZC, Endigo ZCX, Epi-Mek 0.15EC, Expert, Force, Force 3G, Force CS, Force 6.5G, Force Evo, Gramoxone SL, Gramoxone SL 2.0, Gramoxone SL 3.0, Karate, Karate with Zeon Technology, Lamcap, Lamcap II, Lamdec, Lexar EZ, Lumax EZ, Medal II ATZ, Minecto Pro, Proclaim, Tavium Plus VaporGrip Technology, Voliam Xpress and Warrior II with Zeon Technology are Restricted Use Pesticides.

Some seed treatment offers are separately registered products applied to the seed as a combined slurry. Always read individual product labels and treater instructions before combining and applying component products. Orondis Gold may be sold as a formulated premix or as a combination of separately registered products: Orondis Gold 200 and Orondis Gold.

Important: Always read and follow label and bag tag instructions; only those labeled as tolerant to glufosinate may be sprayed with glufosinate ammonium-based herbicides. LibertyLink®, Liberty® and the Water Droplet logo are registered trademarks of BASF. HERCULEX® and the HERCULEX Shield are trademarks of Corteva Agriscience LLC. HERCULEX Insect Protection technology by Corteva Agriscience LLC. Under federal and local laws, only dicamba-containing herbicides registered for use on dicamba-tolerant varieties may be applied. See product labels for details and tank mix partners. Golden Harvest® and NK® soybean varieties are protected under granted or pending U.S. variety patents and other intellectual property rights, regardless of the trait(s) within the seed. The Enlist E3® soybean, LibertyLink®, LibertyLink® GT27®, Roundup Ready 2 Xtend®, Roundup Ready 2 Yield® and XtendFlex® soybean traits may be protected under numerous United States patents. It is unlawful to save soybeans containing these traits for planting or transfer to others for use as a planting seed. Only dicamba formulations that employ VaporGrip® Technology are approved for use with Roundup Ready 2 Xtend® and XtendFlex® soybeans. Only 2,4-D choline formulations with Colex-D® Technology are approved for use with Enlist E3® soybeans. The trademarks or service marks displayed or otherwise used herein are the property of a Syngenta Group Company. ENLIST E3® soybean technology is jointly developed with Corteva Agriscience LLC and M.S. Technologies, L.L.C. The ENLIST trait and ENLIST Weed Control System are technologies owned and developed by Corteva Agriscience LLC. ENLIST® and ENLIST E3® are trademarks of Corteva Agriscience LLC. GT27® is a trademark of M.S. Technologies, L.L.C. and BASF. Roundup Ready 2 Xtend®, Roundup Ready 2 Yield®, XtendFlex®, VaporGrip® and YieldGard VT Pro® are registered trademarks used under license from the Bayer Group.

All other trademarks are the property of their respective owners. More information about Agrisure Duracade® is available at http://www.biotradestatus.com/.

X

You are viewing from

Thank you for visiting the Golden Harvest website. We understand how important it is for you to find agronomic and product information pertinent to your local area. Please enter your zip code or select your area below to ensure you are seeing the information that matters most to you.
Learn more about regions >

CHANGE BY ZIP CODE OR SELECT YOUR REGION

OR
We’re sorry. Golden Harvest is not available in this area. Please try another zip code or contact a Golden Harvest Seed Advisor for more information.

Is this page helpful to you?

How can we improve
this page? (optional)

Can you tell us your
role in agriculture? (optional)

Thanks for the feedback.

We appreciate your participation