Agronomy Update – April 22

Good morning everyone,

Was out delivering/pick up some seed for trials yesterday, and most farms I visited were busy moving/grading/cutting seed.  It definitely appears that spring is ahead of schedule so far…but the weather the rest of April will dictate a lot.

I have had reports from multiple sources that the water table appears to be fully replenished.  Springs are running full, wet spots are still very wet, and streams/brooks are full.  The lack of frost in the ground when rain fell last fall and again this spring meant that a lot of water soaked in rather than ran off, helping to recharge groundwater.  A good sign for the year ahead.


Tuber Diseases

As many are starting to grade and cut seed, it’s a good time to revisit tuber diseases.  It’s important to try and grade out problem tubers before they hit your cutting knives in an effort to reduce the spread of diseases like Fusarium, blackleg and Pythium that can have a significant impact on plant emergence and resultant yields.

Eugenia Banks from the Ontario Potato Board has put together a very good poster with photos of different symptoms of common potato diseases.  Consider providing to your grading staff or even printing off and placing in a visible area if you see fit.  Thanks to Eugenia for allowing me to circulate this to PEI growers.  It is available here in a low-res version.  For a print-quality version, send me an email.


Tuber Size Profile

I know that seed supply for certain varieties is tight this year, and that will have an impact on how growers will manage their seed cutting.  However, I would encourage growers to keep in mind a few key points around seed cutting:

  • Cut seed pieces less than 1.5 oz normally have a yield potential below the cost of production.
  • Cut seed pieces with few eyes in some varieties (ie. Prospect) are more likely to be “blind” and not grow at all.
  • Generally, the larger your average seed piece, the greater potential it has to quickly establish a healthy plant.
  • Avoid cutting seed cold, in order to reduce cracking and rough cut surfaces. This will reduce the risk of secondary infection and enhance suberization.

I am still looking for a couple of growers who would be interested in field trials on seed management.  Particularly, I’d be interested in hearing from growers who would be interested in a small trial looking at:

  • Planting whole seed first, followed by cut seed later versus planting all seed together.
  • Comparing different average seed piece size on a commercial basis
  • Comparing a regular run of seed versus eliminating all seed pieces under 1.5 oz.

Let me know if you’d be interested in a small trial looking at something like this…I’m also open to suggestions, but have some room to take on a handful of seed management trials this spring.


Don’t be in too much of a rush…

Everyone has got the itch to get out and on the land.  You hear that the neighbour is on the land or spreading fertilizer, so you’re keen to get going too…I understand!  Just a couple of things:

  1. Don’t work land or travel on land that is still wet. This will cause all kinds of problems down the road.  It will often cause soil lumps that you’re be cursing as they come up the harvester this fall.  You’re also much more likely to cause sub-surface compaction that can’t be easily fixed with tillage.  Be sure the ground is sufficiently dry before travelling on it.
  2. Ensure fertilizer application is not a waste of money. Spreading nitrogen on land that doesn’t have an actively growing crop, particularly in April, can result in losses due to volatilization (if it sits on the surface) or leaching (if incorporated in the soil).  If doing pre-plant nitrogen application, consider the use of a protected source like ESN/Super-U/Agrotain, etc.  These sources have also been shown to have lower nitrous oxide emissions.  Ensure that you’re able to get the value out of your investment in fertilizer.
  3. The same goes for manure. If you’re spreading manure in the spring, it should ideally be timed ahead of tillage and planting in order to ensure that the nutrients in your manure aren’t lost from off-gassing (ammonia) or lost after heavy rains.  Also ensure that any manure piles are placed in a location where there isn’t a risk of significant water ponding or run-off.  The last thing you want is to have nitrogen, phosphorus, and bacteria in that manure to go to either groundwater or surface water.
  4. Pay attention to soil temperature. Some crops (peas, barley, wheat) can be planted in colder soil without compromising your yield potential.  Potatoes are not one of those crops…particularly if seed is cut.  If you’re planting whole seed, you can get away with planting into cooler soil, but cut seed is vulnerable to set rot in cold soil.  Invest in a soil thermometer (they are pretty cheap) and use that information to guide your planting plans.  Minimum soil temperature at the depth of the seed piece from multiple sources is 7 degrees C (45 F) but many sources I’ve consulted recommend waiting until 10 degrees C (50 F) for cut seed.  Matching your seed temperature in storage to soil temperature to avoid shock to the seed piece has been shown to be advantageous.

Most of this probably just sounds like common sense.  Just remember to go at a pace that makes sense for your farm, for the crops and varieties that you grow.  Being in a rush at the start of the season might cost you time and money later in the season.

Have a safe and productive spring.  I look forward to seeing many of you in the coming weeks when Morgan and I are out soil sampling and setting up field trials.  Feel free to call, text or email with any questions.