Simcoe Ag Breakfast Meeting – May 3, 2017

Synopsis:  Field work is on hold waiting for drier and warmer conditions.  Many parts of the Norfolk to Niagara region have had more rain in the past week (up to May 3) than last years’ growing season total.

denitrification graphic
Figure 1: Denitrification of Nitrogen occurs in saturated soil where soil microbes use the oxygen and convert NO3-N to N2 gas or nitrous oxide. Denitrification is highest when saturated soils occur for prolonged periods with warm temperatures.

Wheat:  September-planted wheat is pushing 2-3rd node and earliest fields could be at flag leaf in the next week.  February warm spells seem to have advanced the wheat crop so that it is up to 10 days ahead of “normal”.  Opportunities for double cropping soybeans are being anticipated.  Late October-planted wheat is less advanced with many fields still tillering.   Tile run wheat demonstrates that wheat does not like “wet feet” with areas between the tiles showing less aggressive growth.  Overall about 10% of wheat fields have had herbicide/fungicide applied.  Most fields have some nitrogen applied, but fields with no N look pale and poor.  Disease levels remain low with a few reports of powdery mildew and Septoria, but conditions have been too cold for disease spread. Scouting continues in for stripe rust so that when it appears, fungicide applications can help minimize yield loss.  Lots of interest in Trivapro for stripe rust.  There is significant weed pressure in wheat, but winter annuals (chickweed, stinkweed, pennycress, etc.) are too advanced for control.   There is a huge reduction in weed pressure in fields with fall weed control compared to those without.  Fleabane is getting big, fast and should be controlled where possible.  If field conditions remain too wet for weed control, there is small comfort in knowing that yield impact would be low.  Yield loss from weed pressure in winter wheat is relatively low (3%) compared to other crops  –  edible beans (54%) followed by corn (48%), followed by soybeans (40%) – according to research data from Peter Sikkema.  However, weeds that go to seed can have future negative impact.

There was discussion about applying a “small shot” of nitrogen to a wheat crop on heavy clay soil in an open period in late February/early March to avoid the frustration of delayed application during a wet spring.  Nitrogen loss from denitrification would be very low (as shown in Figure 1) since losses are highest in saturated soils under warm temperatures.  Loss from leaching would also be low, since growing season conditions – evapo-transpiration –  tends to move nutrients up through the soil profile with water.  Biggest risk for N loss would be in portions of the field where runoff or soil erosion occurs.

When do you give up and not put N on? There is a significant yield response up to just before heading, at anthesis. Although some yield loss will already have occurred, applications of N up to anthesis can be beneficial. Putting urea on after it stops raining is not useful if it doesn’t rain again, the solid particles need some rain to breakdown. If liquid 28% is applied after the rain stops and before anthesis, soil moisture that wicks to the surface will pick it up and it will then move down into the root zone.

Other Field Activities:  Very little corn has been planted, except on the sands.  Dilemma between planting by calendar date or into good conditions has resulted in some corn being pushed.   Field work is occurring on wetter than ideal conditions with more compaction and consolidation of soil.  The Grand River, the Nith river, and rivers in Niagara are high and muddy – evidence of the severe erosion that has occurred this season.  Soil erosion on sloping land with chisel plowing seem to have more rill and gully erosion than moldboard plowing on the contour, although even in fields with un-touched soybean residue, there is significant erosion, due in part to large fields and lack of infiltration.

Manure application is occurring, but very little on the heavy clay soils.  Full storage is a concern on some farms.

Around Niagara many dairy farmers planted cereal rye last fall with intention to harvest as forage this spring.  Harvest will compromise quantity with quality.  Ideal harvest for max digestibility will result in harvesting at flag leaf – before boot stage (maybe this weekend).  In warm temperatures the cereal rye can go from flag leaf to boot stage in 4 days.  As the crop matures beyond the boot stage, the yield volume goes up but quality decreases.  At heading, cereal rye can be good forage for dry cows and heifers.   Some will need to be cut next week, although it will likely be too wet to get on fields.

Alfalfa is growing quickly, but not as far ahead as wheat.  Growers with a 4 cut schedule will be taking a first harvest by last week of May.  Some growers may be short on feed after last year.  Winter kill is not widespread except in areas that had prolonged ponding of water.

Apples in Norfolk doing well right now. Apple yields were not significantly affected with dry weather last year.  Sweet corn coming up on plastic with earliest at 4th leaf stage. Ginseng is currently being fumigated, and 2 and 3 yr old ginseng has emerged.

Weed Control:   Scentless chamomile was a problem last year and looks to be a problem again.  In wheat Boost M, Refine or Barricade give the best control.   In corn or soybean fields a couple passes of glyphosate now is the best control.  Is Scentless chamomile a bigger problem because there is less atrazine being used?   In 2016 the 2 applications of glyphosate that was recommended may not have been applied because dry conditions led to a crop failure and weed control was not a top priority, but this is resulting in bigger weeds and weed pressure this spring. Scentless chamomile was discussed last May, and more information can be found HERE and HERE, and in the table below.

Effectiveness of various control options for scentless chamomile in corn and soybeans


Crop injury may be a risk under current temperatures; reduce risk in wheat by applying in above zero temperature and keep water volumes at 20 gal/ac.

Crop Insurance reporting is now available on-line (24/7).  May 1st deadline has past for reporting crop plans, June 15 is the unseeded acreage; and June 30th deadline to call in acres planted

Next meeting May 17, 2017 at 7:30am at the Shire in Simcoe