facebook_pixel

Better for Soybeans: Fall or Spring Applications?

By Dr. T. Scott Murrell

 

There have been many questions about fall versus spring applications of phosphorus (P) and potassium (K) to soybeans, writes Dr. T. Scott Murrell, International Plant Nutrition Institute Program Director. Does it really matter if P and K are applied in the fall or in the spring? IPNI looked at published studies to see what they could find.

First, there are very few studies that directly compare a fall to a spring application. In fact, only two were found. In both cases, broadcast applications were used.

The first study was conducted in Iowa during 2005 to 2007 and examined P at 20 sites under no-till. Although an application of P did increase soybean yield at seven locations, application timing did not make a difference. So even when soil test P levels were low, soybeans were not sensitive to when the P was applied.

The second study was conducted at two locations in Arkansas from 2009 to 2010 and examined both P and K. Whether K was applied in the fall or spring did not affect soybean yield. At one site in one year, there was an interaction between the rate of P applied and the time of application. The spring application performed better at the higher P rate while the fall application improved yield more at the lower rate. Overall effects were 4 to 5 bu/A. In the other cases, P application time did not affect soybean yield.

With so few data, we don’t have much to go on. With the evidence before us, it looks like soybean may not be sensitive to fall versus spring application times; however, many more studies are needed before we have any certainty.

So what could influence soybean response to P and K application timing? There are lots of things that are site-specific: soil texture, soil moisture, rainfall distribution and intensity, fertilizer placement, fertilizer source, fertilizer rate, and soybean variety to name a few. None of these factors, except fertilizer rate, appears to have been researched in the context of P and K application timing.

So which is better for soybeans? Sparse evidence indicates fall or spring applications produce essentially equivalent results; however, there is a lot of room for discovering what works best under local conditions. Testing this effect for yourself will likely be the most expedient way to find an answer.

 

Dr. T. Scott Murrell is the Potassium Program Director at the International Plant Nutrition Institute.

Topics:

Leave a Reply

Soybeans Stories
Soybeans

Better for Soybeans: Fall or Spring Applications?

November 17, 2017

Does it really matter to soybeans if phosphorus and potassium are applied in the fall or in the spring?

Soybeans

When and Why to Double Inoculate Your Soybeans

November 17, 2017

Double inoculation can help soybean plants form nodules at an optimal rate and time, helping improve their performance potential.

Soybeans

Tips to Prevent Dicamba Drift

June 15, 2017

In a video presentation, Tennessee Weed Specialist Larry Steckel discusses three actions to help reduce dicamba drift and volatilization.

Soybeans

Dicamba Damage Reports Increasing in Arkansas

June 12, 2017

Forty complaints from off-target movement of dicamba have already been reported to the Arkansas State Plant Board, as of June 12.

Soybeans

Cooperation, Preparation Are Keys to Ag Sustainability

May 5, 2017

Georgia’s Stanley Culpepper outlines the training efforts for auxin herbicides in the state and praises the people who make it all work.

Soybeans

Research: Some Applicator Hoses Can Retain Auxin Residues

April 19, 2017

According to research in the journal Weed Science, residues of the auxin herbicides dicamba and 2,4-D can be retained by certain types of applicator hoses and injure sensitive crops.

Soybeans

Managing Target Spot in Soybeans

April 12, 2017

Following a troublesome infestation of target spot in soybeans in 2016, there are several things that growers need to keep in mind for managing the disease in 2017.

Around The Gin
Product News

Indigo Offers Premium for Indigo Cotton Production

January 9, 2018

Indigo Ag has announced a new program that offers significant price premiums for U.S. cotton growers who contract to grow Indigo Cotton.

Product News

New Bayer Varieties Focus on High Yield, Adaptability

January 5, 2018

Bayer releases five new FiberMax and Stoneville varieties for introduction in 2018.

Product News

New PhytoGen TRiO Guards Cottonseed Investment

January 3, 2018

New PhytoGen TRiO seed treatment helps provide early season protection for young cottonseed from diseases, insects and nematodes.

Product News

Americot Adds Seven to Sales, Research Teams

December 20, 2017

Americot has added seven new sales and research associates to the company’s staff across the Cotton Belt.

Product News

Seven New Varieties in Deltapine Class of 18

December 11, 2017

Seven new varieties – including five Bollgard 3 XtendFlex offerings – join the Deltapine product lineup as the Class of 18.

Product News

Special Roundup Ready PLUS Incentives for Arkansas

December 7, 2017

Monsanto is offering a special Roundup Ready PLUS Crop Management Solutions platform in Arkansas for 2018 for growers planting XtendFlex cotton and Roundup Ready 2 Xtend soybean varieties.

Product News

Monsanto Sets 2018 Crop Protection Incentives

December 5, 2017

Monsanto will provide multiple tools, resources and products to help cotton and soybean growers maximize weed control in 2018.

Product News

Praxidyn’s Mixmate Named a 2018 AE50 Award Winner

November 27, 2017

The American Society of Agricultural and Biological Engineers has recognized Praxidyn's Mixmate portable ag chemical blending and recordkeeping system with a 2018 AE50 award.

Latest News
Soybeans

When and Why to Double Inoculate Your Soybeans

November 17, 2017

Double inoculation can help soybean plants form nodules at an optimal rate and time, helping improve their performance potential.

Soybeans

Better for Soybeans: Fall or Spring Applications?

November 17, 2017

Does it really matter to soybeans if phosphorus and potassium are applied in the fall or in the spring?

Soybeans

Arkansas Researchers Share Dicamba Volatility Studies

August 11, 2017

Work done by University of Arkansas weed scientists has found that every dicamba formulation tested this spring and summer demonstrated a level of volatility.

Opinion

No One Reason for “Frustrating” Dicamba Issue

July 18, 2017

Tennessee Weed Specialist Larry Steckel has walked hundreds of drift-damaged soybean fields in the past few weeks. He shares some opinions about possible reasons for the problem.

Soybeans

Tips to Prevent Dicamba Drift

June 15, 2017

In a video presentation, Tennessee Weed Specialist Larry Steckel discusses three actions to help reduce dicamba drift and volatilization.

Soybeans

Dicamba Damage Reports Increasing in Arkansas

June 12, 2017

Forty complaints from off-target movement of dicamba have already been reported to the Arkansas State Plant Board, as of June 12.

Soybeans

Cooperation, Preparation Are Keys to Ag Sustainability

May 5, 2017

Georgia’s Stanley Culpepper outlines the training efforts for auxin herbicides in the state and praises the people who make it all work.

Soybeans

Research: Some Applicator Hoses Can Retain Auxin Residues

April 19, 2017

According to research in the journal Weed Science, residues of the auxin herbicides dicamba and 2,4-D can be retained by certain types of applicator hoses and injure sensitive crops.

Soybeans

Managing Target Spot in Soybeans

April 12, 2017

Following a troublesome infestation of target spot in soybeans in 2016, there are several things that growers need to keep in mind for managing the disease in 2017.

Soybeans

Soybean Oil Used to Develop High Tech Graphene

March 20, 2017

A team of Australian scientists has used soybean oil to make graphene – the strongest and thinnest type of carbon with good electrical conductivity.

Soybeans

Pigposium III: Getting Off the “Resistance Treadmill”

March 7, 2017

Nearly 300 attendees at the University of Arkansas’ Pigposium III heard options to help them beat the “resistance treadmill” when it comes to pigweed control.

Soybeans

Crowding Out Weeds

February 24, 2017

Arkansas soybean specialist says narrowing your rows can have a big impact on weed control.

Soybeans

Control Italian Ryegrass Early

January 25, 2017

An early winter burndown for glyphosate-resistant Italian ryegrass can provide growers time and flexibility in deciding how to control escapes prior to planting.

Soybeans

Bayer, MS Technologies Get China Approval for Balance GT Soybeans

January 25, 2017

Bayer and MS Technologies have received import approval from China for Balance GT soybeans.

Soybeans

Cotton/Soybean Rotation Reminders

January 9, 2017

When rotating soybeans onto cotton acres, growers should keep the need for seed inoculation, as well as a close eye on weed control options, in mind.