Agronomy Update – Sept 4

Hi everyone,

Thank you to everyone that came out the last two days to our AIM Field Tours around the province.  It was great to be able to show you some of the trials that we are working on in partnership with growers.  We had some great conversations about the trials, best management practices, and the status of the crop at the moment.

I have uploaded the three factsheets from the tours to the Agronomy Site if you’d like to take a look at them.  If you have any questions about any of the individual trials that we are working on, please feel free to contact me!

A special Thank You to the growers that allowed us to visit their fields this week, as well as all of the growers that participate in trials with AIM.  Without involvement of growers, we would not have an AIM program.  I sincerely thank you for your partnership and interest.

Weather Update:

Looks like many folks got more rain yesterday/last night than was predicted.  Too late for some varieties/crops, but much needed for a lot of Russets that are bulking now.

Some totals from Thurs/Friday up to 10:00 am from a mix of Ukko Agro sensors and Weather Underground stations:

St. Louis               52.3 mm       Kensington                    13.0 mm
Elmsdale               57.4             Emerald                         14.7
Springfield West    47.2             Springfield                     24.9
West Cape             38.4            New London                    7.4
Foxley River           43.7            Charlottetown                 22.4
Northam                 20.3            Savage Harbour             13.0
Central Lot 16        14.0            St. Peters                        25.4
Miscouche              23.9           Avondale                         19.8
Bedeque                   7.4           Rollo Bay                        19.3
Freetown                 11.9           Souris                             16.6
Augustine Cove       16.0          Panmure Island               28.7

Looking at August:

 Table 1: August 2020 growing degree days (GDD) and rainfall amounts (mm)

Location GDD (>5oC) Rainfall (mm)
Elmsdale 442 44
Cape Egmont 479 62
Borden Carleton 487 82
New London 451 67
Charlottetown 465 66
Alliston 462 54
Souris West 446  70


For GDD, most stations are 30 to 40 GDD higher than historical average.  Rainfall in August was between 25 and 50 mm less than historical average for most communities, and almost all of that rain came in the last couple days of August.


Looking at rainfall for the season:


Table 2: Accumulative Rainfall for 2020 Growing Season

Rainfall (mm)

Location May June July August Totals
South Lake- East Baltic- East Point 49 23 86 70 228
Charlottetown 63 30 51 66 210
Summerside-Miscouche 59 17 38 63 177
Elmsdale 65 15 58 44 182

Spore Trapping Update:

A number of spore trapping sites have ended their service for the summer, as the crop is either been killed (chip stock/table stock) or is going down and last fungicides are being applied.  Of the sites remaining, early blight (Alternaria solani) spore counts are generally low, and have been for the last couple of weeks.  With cooler, wetter weather setting in, we are past the prime time for early blight/brown spot.  There continue to be some high numbers for grey mold (Bortrytis cinerea) spores in certain communities, but I have not heard from anyone concerned about grey mold in their canopies.

We have not had any spores captured for late blight in PEI, and there have not been any found in NB or Maine either.  The closest report of late blight this season has been the report of late blight in one field in Southern Ontario recently.  Take this lack of spores/disease into account when planning your fungicide applications in the next couple of weeks.

Cover Cropping Update:

Getting lots of calls/texts/emails about cover cropping in the last couple of weeks…awesome!  Keep the questions coming!

For those planting brassica species (tillage radish, oilseed radish, mustard) as a cover crop…get them in soon.  Literature says Sept 15th is the cut-off for good establishment here in PEI.  My experience with growers is that Sept 10th is probably closer to the real cut-off for really good establishment.  The later you go, I would up your seeding rate a little.  I would also recommend planting a grain like barley or oats with the brassica, in case you don’t get a super catch of radish/mustard.  Maximize that biomass, both above ground and (more importantly) below ground.

Have had some questions about planting sudangrass in September….don’t do it.  Not enough time.  It will establish…but it will be done on the first frost we get.  Grains/grasses/brassicas/winter peas are all better options now.  Likewise, buckwheat is not a good fall cover crop.  It does not stand up to frost at all.

Morgan and I are still looking for a few growers interested in doing field trials on cover crops after potatoes for our Living Labs project.  This comes with some funding to help off-set the cost of seed/tillage, and we do all of the sampling.  Give Morgan or I a call if you’re in the Kensington North, Dunk/Wilmot, or Souris Watershed areas and would like to talk about options.

Looking for Trial Partners:

  • For an AIM trial, I am looking for growers who would have planted a commercial field of a processing variety with seed between 1.5 and 3.0% PVY at planting. We are doing a small trial looking at the potential for mechanical PVY spread in wheel tracks.  If you have a field that might fit these criteria, please give me a call or send me an email.  I would like to inspect fields immediately for this trial.
  • Any growers interested in doing Fall Hilling this August/September in advance of potatoes next year…I’m looking for some more fields to continue our AIM research into use of Fall Hilling.  If you’d like to know more and want to discuss how we can cooperate, please give me a shout!  Need to get these fields identified ASAP!
  • In partnership with the PEI Dept of Ag and AAFC, we will again be doing a fall survey of Island fields for Verticillium and root lesion nematodes as part of the CanPEDNet project on Potato Early Dying.  We will be sampling fields in late October.  I’m looking for fields all across the Island that will be in Russet Burbank or similar susceptible varieties next year.  Your chance to get a free Vert/nematode test on your field!  We then take the 4 best and 4 worst fields from the survey and follow them next year (including yield samples) to help improve the thresholds for both Verticillium and root lesion nematodes.

Have a great long weekend, and I hope that your spuds keep adding some yield as we move through September.  As always, feel free to give me a call or send me an email if you have questions or want to discuss anything in these updates.