Included: Weed control, armyworm, corn field notes, double crop soys and more.
Synopsis: Rainfall varies widely across the region, from 0.5 to 4.5”. Most areas have excellent moisture now, with a few dry pockets and a few waterlogged areas. Crops remain well ahead in development, with a suggestion that Michigan Sugar will open the plant a full month ahead of schedule. Armyworm is present in every wheat field, with significant pressure of small larvae in many fields. Fusarium control on wheat is complete, with 35 to 100% of the acres treated depending on region (average 70%). Sidedressing is underway and will resume full force when soils dry. Nitrogen soil test results show a small opportunity to reduce N applications on loam soils, but with high yield expectations most growers will stay the course on N. Soybean planting is all but finished with a few replants due to crusting on heavier soils. Stands look great. Lots of chatter on double crop soybeans: seed will be available at a reduced price for growers.
Weed Control: Lots of spraying to be done. Some growers have chosen to wait for the second flush of weeds and try to get by with only one spray. These fields are a MESS and will have yield reduction. While soil applied chemistry did not have enough rainfall for activation, and most fields need resprayed, the level of suppression from these herbicides is impressive. In one field an unsprayed strip had foxtail “as thick as the shag carpet in my 1976 van” (Chad Anderson), and taller than the corn, where the sprayed field beside had patches of foxtail that were only 1” tall. Even without activation 50 to 80% weed control and greatly reduced growth was achieved.
Weed of the year is curled dock. There seems to be lots of it out there, especially on clay soils, and it was advanced enough that control seemed impossible. Most of the weed escapes so far are grasses, which do better under dry conditions. Lots of proso millet and fall panicum showing up, along with the regular grass problems. Some misses with glyphosate on lambsquarters. In some cases it can be tracked back to too much water (10 gal/ac should be MAX with glyphosate).
Questions continue to come in on control of volunteer corn, and the right rate. For Assure II, keep the surfactant rate up at the low rate of herbicide (0.1 l/ac). If tank mixing with glyphosate, consider the glyphosate to be ½ of the surfactant (Roger Bourassa).
Corn: Stands are generally good, but more variability than ever before. Corn planted April 25/26 is the worst, with some dead seeds (5-20%) from what appears to be severe chilling injury. Early April corn is excellent. There is purple corn and rootless corn out there as plants struggle to develop roots in dry soil. Yellowing and necrosis of lower leaf margins has been noted, and is most probably potassium deficiency. Some significant yellowing and bending or snapping of corn after the rain, due to rapid growth. There is some varietal specificity to this issue. The corn will grow out of these symptoms and yield impact should be minimal. Side dressing is well underway, and should wrap up quickly if weather permits.
Michiganis catching western bean cutworm moths but none have been reported in traps inOntarioyet. The “Yellow Striped Cutworm” moth also seems to enjoy the pheromones of the WBC traps, so don’t confuse YSC catches with WBC moths.
Armyworms: High levels of small armyworm are present in many wheat fields. “The ground is alive with ¼” armyworm” (Al McCallum). SCOUT! 5 larvae under 1” in a square foot is the threshold. 19” of row equals 1 square foot. Early control is essential to achieve best possible efficacy and least yield loss. Pre Harvest intervals are becoming a concern with some insecticides. Control products and days to harvest can be found at https://fieldcropnews.com/2012/06/armyworm-are-marching/
Soybeans: Wetter areas have the last few fields of soybeans still to plant, but should be done by weeks end if no additional rain falls. A few bean replants have been necessary on heavy clay soils with pounding rains, but all in all the crop looks excellent. No reports of bean leaf beetle or soybean aphids to date.
Double Cropping Soybeans: The interest in double crop soybeans continues. Seed supplies will be available, with several seed reps at the meeting indicating there would be discounts for seed purchased for double cropping purposes. There may well be double crop soybeans planted this year at an earlier date than the first crop soybeans were planted last year. The question was raised about the value of treated seed in double crop soybean production: while the value may be somewhat reduced, there may be significant merit in seed treatments if soybean aphid numbers are high. Often what makes logical sense to us turns out to be wrong, and when planting with a limited development window, such as double crop soybeans, gaining an extra days development or removing a stress can have significant implications. It will be up to the grower to decide, although some companies will not sell untreated seed even in a double crop scenario. Where growers are planning on double cropping they should leave a minmum of 4” and preferably 6” of wheat stubble. Wheat stubble will cause soybeans to stretch more for sunlight, increasing the first internode length, and prevent podding very close to the ground.
Other Crops: Early sugar beets in 30” rows have almost canopied, at least two weeks ahead of schedule. Stands look exceptional, with tremendous yield potential if weather holds. There is a concern that Headline resistant cercospora leaf spot may have developed (unconfirmed), but every grower should be tankmixing with mancozeb to avoid resistance developing. This is no different than avoiding resistance with herbicides. Transplanting tomatoes are wrapping up, and all vegetable crops look good. Pea harvest is just underway.
Huron Research Station Tour: June 26th, 7:00 am
Diagnostic Days: July 4/5, 1 877 424 1300
Soil Management Day: August 2nd, Dunnville 519 537 6621
Crop Insurance deadlines:
June 15: Last day to report unseeded acreage.
June 30: Spring seeded final acreage reports due.
July 10: Premiums due.
Publications:
Publication 812 – Field Crop Protection Guide is available at any resource center, or by calling ServiceOntario Publications, 1-800-668-9938 or 416-326-5300.
CropLine – 1-888-449-0937
CropPest Website – http://www.omafra.gov.on.ca/english/crops/field/news/news_croppest.html
Crop Technology Contacts:
Adam Hayes, 519-674-1621 adam.hayes@ontario.ca
Peter Johnson, 519-271-8180 peter.johnson@ontario.ca
Albert Tenuta, 519-674-1617 albert.tenuta@ontario.ca