Notable Quotable: “Corn will tassel on July 17th at 2:35pm.” – Gilles Quesnel
Rain blessed parts of the region in the past week but often not enough to be effective, and many areas are still drier than desired. Some wilting has been observed on lighter-textured ground, but many heavier soils are still holding good moisture. We need rain next week for crop conditions to continue improving.
In Ottawa, 1075 CHU have accumulated since May 1st, 100 units above average for this time of year. On the other hand, accumulated precipitation sits at 115cm, 25% below the 30-year average.
Most new alfalfa seedings are looking good. Some spring seedings are a bit spotty – planting equipment quality and calibration are important.
First cut has been variable. Some have been getting very good yields, others are a bit disappointed. Most areas got reasonable rain after first cut and are growing back strongly. The western part of the region has been generally drier.
Leaf hopper populations are building slowly. They could be locally variable, but overall much less concerning than at this point last year. Pea aphids have been reported in some fields. Aphids can do noticeable damage in dry years, but don’t cause the same stunting effect as leaf hoppers, which generally require a cutting to reactivate a severely burned plant.
A strong response was observed in a field of alfalfa with a blend of sulfur and phosphate (10lbs ammonium thiosulphate and 50lbs phosphate). Dry and cool conditions as we’ve seen recently limit the soil sulfur supply as it is tied to organic matter mineralization. Those wanting to trial strips of sulfur fertilizer should be aware that, in addition to this weather effect, sources that include nitrogen can make results difficult to interpret.
Winter wheat is starting to turn colour, but is not quite at the dough stage. Development is progressing quickly, though kernels are not yet changing colour.
No armyworms have been found, and the trapping network in Quebec is not picking up many moths. Very little stripe rust has been observed, and cereal leaf beetle populations are low compared to previous years.
Spring cereals are in a bit of a vulnerable stage heading into the above-30 C temperatures of the coming weeks. It will be pushing through its maturity stages quickly, so be advised with respect to application timing. If heads are short now, hot conditions ahead will cut elongation short.
Growers who are split applying nitrogen at flowering looking to increase protein have mostly finished their last streamer application in the past week. Rates should be adjusted by variety with regards to lodging susceptibility. About 70% of spring wheat will be sprayed with fungicide by the end of the week.
While there were early-season concerns about stands and plant populations, most corn fields are looking good, though some are showing signs of drought stress. There is plenty of moisture left in heavy soils, but compacted layers can limit root access to this water. There will be prayers for rain this week but overall, spring conditions have been good for corn.
Most side-dress nitrogen is on, much of it added in the past week. There was good discussion on the merits and interpretation of using pre-sidedress nitrate test (PSNT) results for determining application rates. Recommendations for side dress can be found in OMAFRA publication 811: Agronomy Guide, but questions remain about calibration of the test for split applications at more advanced crop stages, and false recommendations are possible if sampling hot spots or fields receiving over 27kg/ha (30lbs/ac) N before sampling.
While many stands looked variable at emergence, most have pulled through. As elsewhere in the province, soybeans planted early are doing much better than those planted later into drier conditions. Many of these were planted too deeply – up to 3 inches – in an attempt to plant into moisture. These have struggled to emerge, and one report observed heavy wireworm damage before emergence, followed by phytophthora. There was also a report of replant due to seed corn maggot in a 30ac field of untreated soybeans. Overall, plant populations seem higher than in previous years, attributed to timely rains and in some cases, drills still set for last year’s large seeds.
Pre-emergence herbicides are holding well, though they are less effective where applied in dry conditions. Post-emergence weed control is ongoing. Nodulation is good where it has been checked, and soybean aphids have yet to make an appearance.
With the previous statements on variability between fields in mind, there are a lot of soybeans at the V4 stage, and the most advanced have already started flowering. Growers should have their disease control plans in place, as fungicides should be applied within this window, between R1 and R4 according to leaf disease conditions. Two-four flowers per plant is a good time for early applications, which are important in lush stands, and University of Guelph research recommends R2.5-3. Treatment decisions for white mold need to be made earlier – at two flowers per plant – as fungicide must be present before spores land on the flowers to be effective. There are no concerns with product supply.
Markets are morose, as trade conditions continue to sour between the US and China in particular. China will impose a 25% tariff on US soybeans effective July 6th, and is strongly prioritizing non-American soybeans. This is a problem for Canadian growers as well as our soybeans are marketed through Chicago.
Southwest Crop Diagnostic Days – Ridgetown Campus, July 4 or 5, 2018
FarmSmart Expo 2018 -Elora Research Station, July 12, 2018
Eastern Ontario Crop Diagnostic Day – Winchester Research Station, July 19, 2018