Agronomy Update – April 14th

Hi everyone, and Happy Easter to all who celebrate!

It’s been three sunny and relatively warm days in a row in PEI, and land is starting to dry up.  Growers are getting geared up receive seed, fine tune machinery, and get necessary inputs lined up and delivered.  Usually, it’s a time of optimism in the industry.  With the painfulness of border closures this winter as well as the high cost of inputs this spring, that optimism is palpably muted.  However, I hope that you all have a great spring with cooperative weather and great health to you and your employees.

A few things to pass along before the long weekend…


Fertility Credits:

I’ve been talking a lot about fertility the last couple of updates, but it’s at the top of mind for a lot of folks this spring.  A few resources to share:

Manure Calculation Worksheet:  If you are using manure as part of your nutrient management program, play around with this Excel spreadsheet from the PEI Department of Agriculture and Lab.  All you have to do is enter the results of a manure nutrient analysis test and your application rate and it will give you the lbs/acre of N, P, and K that you can expect that manure to make available to your crop this year.  It comes with some examples for different types of manure.  Give it a try!

N Credits for Legumes:  Did you grow a hay crop with legumes last year ahead of potatoes this year?  Are you trying to figure out how much nitrogen credit this is worth?  It can be difficult to pin this down exactly, but there are some relevant guides to help you figure out how much N credit you should account for in your fertility plan.

Here is the table provided by the PEI Department of Agriculture & Land:

Note that the credits from alfalfa are roughly double what you would expect from red clover.  Also note that with a good stand of ryegrass, you may need to add nitrogen to make up for that extra residue.

Here is a similar credit table from the OMAFRA Soil Fertility Handbook:

Again, note that there is a difference in credits depending on whether it is an established forage stand and what level of legumes are in it.  Also, you’ll see that there is a difference between field corn and other crops.  This is because field corn’s N requirements occur later in the growing season than most grains and oilseeds.  In this way, it is similar to potato in terms of the time of maximum N requirements.  The OMAFA handbook explains these N release curves using a handy chart (below):

As you can see, the N credit coming from legumes is not available early in the season, but by mid to late summer, that N is much more available.  This is the time of peak N uptake in potatoes…so keep that in mind when determining your fertility plans.  If you have any questions or would like to talk through your specific nutrient management plans, feel free to contact me.


Interested in Trials?

Do you have something you’re interested in doing some trial work on?  Give me a call or shoot me an email…I’d be happy to discuss it with you!

A couple of areas I’d be very interested in finding some trial partners on:

  • N reduction in seed production (particularly newer varieties)
  • Manure management
  • Bruise reduction/seed handling

Chlorothalonil Survey – Deadline Tomorrow:

The PEI Potato Board would appreciate your assistance by completing the Chlorothalonil Grower Use Survey and returning it by Friday, April 15th.   This information helps the Canadian Potato Council (CPC) to put together data that many help build a case to keep Bravo/Echo usage on potatoes in Canada.  Individual grower responses are anonymous and will not be shared with PMRA.

We are requesting your input in this potato survey that will greatly assist in providing PMRA with information that they can use to refine their risk assessments for chlorothalonil (BRAVO/ECHO). The survey has 15 questions that will take approximately 10-15 minutes to complete. Responses to these surveys, which are anonymous, are requested by no later than Friday April 15, 2022.

 The Link to the Potato Survey is:

Have a great long weekend, everyone