05 Sep Agronomy Update – Sept 5th
Hi everyone,
It remains extremely dry across most of the province. Much of West Prince and East Prince received 20 mm or less in August, which is less than 25% of regular rainfall amounts. Amounts are better east of Hunter River, but it is still quite dry across most of the province. Some fields are hanging on but need rain immediately. Others are past the point of no return and are already senescing quickly.
Insect issues:
I’m hearing from several growers that numbers of aphids, tarnished plant bugs, and leafhoppers are high in certain areas. With canopies already under stress, these insects can further compromise plants quickly. Please keep a close eye on your fields and consider appropriate insecticides when reaching or exceeding thresholds.
A lot of seed acres have already been killed, which is good because aphid numbers rocketed up last week to the highest levels of the year. This included the arrival of green peach aphids after being absent until last week. If you still have seed acres not killed, a non-pyrethroid aphicide (something other than Silencer, Matador, Decis) is recommended to keep aphids under control. Green peach aphids are close to 100% resistant to lamba-cyhalothrin and other pyrethroid aphicides.
Spore Trapping Update:
- Late Blight has not been detected in PEI this week in either Spornado or Airspore programs.
- Foliar late blight has been found in ON, QC and ME this season, but not in NB or PE. While the hot and dry weather of the last couple of weeks has been hard on the plants, it has not been conducive to late blight development.
- The number of farms participating in Airspore decreased significantly starting this week (end of season) so it’s not useful to provide regional averages. Early blight and brown spot numbers are zero on most fields, with a few fields showing higher numbers. We are largely past the point of management for Alternaria now.
- Bortrytis spore counts decreased this week for both the Airspore and Spornado programs over the last two weeks. This is undoubtedly due to the hot, dry weather with very little humidity. There is still grey mold inoculum around and some evidence of grey mold in the bottom leaves of some varieties, so manage according to the risk on your farm.
Getting ready for cover cropping:
They dry weather has made it challenging to start working land and getting cover crops seeded, but I know that a lot of producers are starting to look at getting fields tilled and cover crops established before potatoes right away. Then, growers will be looking at cover crops following potato harvest.
On the PEI Potato Agronomy site, I have a PDF of a presentation I did on fall cover cropping based on experience from grower trials over the past number of years.
Some fall cover options to seed now until mid-September:
- Oilseed radish
- Tillage radish
- Brown mustard
- Spring cereals (oats, barley, wheat, etc)
- Winter canola
- Winter cereals (rye, barley, wheat, triticale)
- Peas
- Kale
- Mixes of any of these species
From mid-Sept to first of October, the options start getting more limited…mostly spring cereals and winter cereals. After the first week of October, I would suggest sticking mostly with winter cereals in order to get a strong establishment, unless we have a warm, long fall. Spring barley/oats/wheat won’t have much time to establish after Oct 7th in most years.
There are a number of producers with spring wheat or barley that failed mycotoxin tests this summer. If this can’t be sold for animal feed, it can be used as a cover crop without much risk of multiplying Fusarium, as it will winter-kill before it goes to head. A good use for some grain that might not have another home.
An additional tool for cover crop selection is the Cover Crop Selection Tool hosted by Perennia in NS. It uses the data from the Eastern Canadian Cover Crop Tool that was previously developed by AAFC and others but in a new format. You can access it free of charge, you just need to create a free account.
Here’s hoping for some rain this weekend!
Ryan