Most of the area is under hot and dry conditions. Spotty thunderstorms have resulted in variable rain ranging from no rain to 5 inches at Stoney Point (Essex). About 1/3 of normal total crop heat units (chu) will be accumulated by end of June. Considering cold temperatures to start the season, current chu are within a few days of long-term average. This year is a testament to the value of good crop rotation and good field drainage.
With the current heat and dry conditions, the wheat crop has advanced more quickly with shortened grain fill period, and many fields are beginning to turn colour. In early planted fields in Essex, harvest is set to begin in the next 2 weeks. Eroded knolls and sandy areas of fields are “burning up” and turning white prematurely. Dry conditions will not impact overall yields as much as high temperatures. Temperatures over 30oC will have a negative impact on yield, however, in much of the area temperatures have not exceeded 30oC. In some fields “head snag” and heads where grain fill is not occurring have been observed. This is likely a result of cold stress in the spring. Pre-harvest scouting for Fusarium head blight (FHB) shows low risk, currently. Fields have the odd plant with FHB, but generally at very low levels.
Peter Johnson commented on the increased observation of a variety of grasses in wheat fields, including wild oats, brome, chess, bluegrass and Roughstalk bluegrass. In addition, in some fields there is a large population of foxtail in the understory of the crop canopy that will become evident at harvest. It is important to identify and document the species of grasses so that next time the field is rotated to wheat, the proper fall controls can be applied. For example, pyroxsulam (Simplicity) applied in the fall will control wild oats (?) and brome, but not Bluegrass. A pre-plant(?) application of pyroxasulfone + carfentrazone-ethyl (Focus) will help control bluegrass. Rough stalked blue grass is a species that is important to document. This year it has become a target for armyworm in some fields due to its thick growth pattern. Armyworm are still being sprayed for as they “march” from wheat fields to spring cereals, especially in the Grey-Bruce area. Growers/consultants are asked to document where armyworm control was necessary by completing a short survey found at: https://arcg.is/WXCGb. Results from this survey will help better the regional differences in armyworm outbreaks.
Some corn looks tremendous – “shoulder high by July”. May 1st planted corn in Essex is at V10 stage and is expected to tassel before mid-July. Western Bean Cutworm (WBC) traps are being setup with monitoring adult flight activity beginning this week. There are many different micro- nutrient deficiencies showing up that we normally don’t see. Magnesium deficiency is showing up on some clay soils and manganese and sulphur deficiencies on sandy loam soils where these deficiencies would not be expected.
Soybeans and Edible Beans
Soybean growth is still behind, especially in fields with replants. Dry conditions are resulting in some manganese deficiencies visible. In areas that haven’t received rain, spider mite population are expected to increase as wheat is harvested. Soybean aphid populations are also starting to climb in some areas.
Herbicide carryover in soybeans and dry edible beans have been a more significant problem this year. Dr. Peter Sikkema has had more calls on herbicide injury, especially on dry beans this year than ever before in his career. Most injury is related to the cold temperatures in early June, and most injury is related to poor metabolism of Group 27 carryover in 2019. Group 27 herbicide carryover is different with different products, but market share of group 27 herbicides is affecting the perception of greater injury with some products. Acuron + Callisto are showing more carryover because they were used more in 2019. Herbicide carryover injury is more common on low organic matter soils, low pH and coarse-textured soils. Weather conditions in the year of application affects potential for greater carryover – especially when herbicides were applied late in a late, wet growing season combined with mid-season hot and dry conditions. Carryover injury appears worse on fields with heavy residue cover, but residue is not considered to impact group 27 herbicide carryover, but more likely the slower growth of current crops is resulting in slower plant metabolism. When scouting a field that appears to have carryover injury, it is important to observe where the injury is occurring. With group 27 herbicides the injury occurs at the growing point. Fields with injury appearing on the unifoliate margins are more likely experiencing injury from group 15 herbicides.
Peter S has made 4 calls on off-target group 4 herbicides, which is concerning. In general, growers have done a good job across all sectors, but to have access to these herbicides in the future, everyone must use them properly. In these cases, the damage appears to be more drift related than inversion. Symptoms of dicamba on soybeans and dry beans involve cupping of bean leaves while 2,4-D on soybeans dry beans show more elongated narrow leaves.
Field research on glyphosate resistant weeds this year is showing results consistent with past 10 years. For Canada Fleabane, the herbicides; Integrity, Marksman, Acuron and combinations are working well. Post applications of Callisto are working well. For soybeans, glyphosate plus Aragon, Sencor, etc., are working well. Bromoxynil is more variable this year.
There have not been any new reports of glyphosate resistant water hemp since last year when it was found east of Toronto. 10 Ontario counties have reported glyphosate-resistant water hemp and in many fields Peter S. has been surprised how many plants have 4-way resistance – up to 5% of the plants. He expects this will become a bigger problem over time, especially with limited control options.
Albert Tenuta discussed the various diseases to be scouting for:
Soybean cyst nematode (SCN): – 32 days after planting saw soybean female cysts appear on roots, usually occurs between 27-35 days post planting. Dry conditions will promote more reproduction of cysts on roots.
Sudden death syndrome (SDS): wet weather early in the season followed with dry conditions sets up scenario for fusarium root rots now and by about the 3rd week of July we could see typical SDS interveinal chlorosis symptoms following rain events. . Early season fusarium root rot symptoms can resemble SDS especially when wet, dry cycles occur. Testing for virus has been done to rule out virus vs herbicide carryover injuries. Based on the amount and wide distribution of symptoms in these fields, most are expected to be herbicide carryover or drift and not virus.
Tar Spot: no tar spot identified, but it has been identified near Michigan border in 2019. Tar spot monitoring system with US states has been set up but nothing seen yet. Where tar spot overwinters, symptoms from infected plants would be expected to start showing up in the next couple weeks. The impact in Ontario would be later since the disease is not established here yet. Scouting for tar spot and other disease will continue in 2020 especially along Michigan-Ontario border (including north of London for disease coming from Michigan thumb area). Tar spot scouting reports for 2020 can be found at https://corn.ipmpipe.org/tarspot/
Northern corn leaf blight inoculations start in the next couple of weeks for testing
Rust in wheat is coming in later so minimal impact expected.
White mold: is weather related. Sporecaster Tool updated for use the aid in white mold control. For link to the tool: https://www.canr.msu.edu/news/sporecaster_new_white_mold_risk_prediction_smartphone_app_now_live
DON cast tool for corn is in development with Dr. Dave Hooker and WIN.
Agricorp Report: Leon Walczak gave the report reflecting mostly Essex, Lambton, Kent but also including Norfolk, Haldimand and Niagara (?)
June 30 is the main reporting deadline for most crops. Please use the website. There is one extension on processing crops.
Damage reports (January 1 to Jun 29):
winter wheat: 417 reports covering 26,086 acres; up 8 reports and 2,872 acres from 2 weeks ago with the main reason being winter kill and excess moisture
Corn: 356 reports covering 39,806 acres; up 66 reports and 6,864 acres from 2 weeks ago with the main issue being excess moisture
Soybeans: 690 reports covering 73,750 acres; up 357 reports and 30,666 acres from 2 weeks ago mostly in Essex and Lambton due to high rains in Essex and high moisture leading to crusting.
COVID19 protocols are important as we go into wheat harvest. Dale Cowan commented on expectations for most grain elevator facilities. They include:
* Social distancing
* No one can enter the scale house, etc.
* Stay in vehicle
* Wear masks
Different municipalities have different rules therefore people need to be aware when travelling around, ie hauling grain across counties to different end users. Let’s keep everyone safe and keep businesses working!
Ontario Virtual Diagnostic Days
Southwest Crop Diagnostic Days (Ridgetown), FarmSmart Expo(Elora) and Eastern Crops Day (Winchester) will be combined into one virtual event in 2020 in response to the COVID-19 situation.
July 15 start, every two weeks for 1 hr and have 2-5 individual topics within each. 8 CEU credits will be applied for the series. Registration for those wanting CEU credits will open shortly at https://bdc.ridgetownc.com/useservices/conferencemanagement/southwest-crop-diagnostic-days/