By Top Crop Manager
May 30, 2014, Ontario – Provincially, 70 per cent of intended corn acres are now planted, writes Greg Stewart in the latest field crop report from OMAF.
Planting is 90 per cent complete in the south and 50 per cent in the north, according to Brian Hall. Heavy rains in several areas has caused crusting and emergence issues. Check stand emergence 10 to 14 days after planting. An acceptable target stand is three to five plants per square foot. Flea beetles are emerging from overwintering. Begin scouting emerged canola every two to three days for flea beetles. Threshold for control is 25 per cent leaf feeding. Swede midge are at threshold numbers at Elora, and none at locations further north. Begin monitoring swede midge traps every two to three days once canola has one true leaf. Initial threshold for control is 20 midge total per four traps. Don’t wait until damage is visible! Updates on a province wide midge monitoring project will be posted at http://www.ontariocanolagrowers.ca/.
Early fields in the southwest are heading! Peter Johnson reminds growers to apply fusarium sprays shortly. Timing fungicides will be a challenge due to the unevenness of the crop. Target day 5 of the earliest 25 per cent of the field, the latest possible timing for fusarium control. Some heads will not be emerged, but earliest heading plants have the highest yield potential. The majority of yield increase is from leaf disease control even if all heads are not emerged. Sulphur deficiency continues so where needed apply 3L/ha (3 gals/ac) of ammonium thiosulphate by itself. Adult cereal leaf beetles (CLB) are close to threshold in traditional areas – so scout! One CLB/stem warrants control. Where virus or nitrogen deficiency is evident between tile runs on heavy clay soils consider 34kg/ha (30 lbs/ac) of added N. There is no control for virus. Early spring cereals have tillered well, with up to six tillers per plant in lush fields. Stem elongation is beginning. Later fields have just been planted. Early fields should have N and weed control applied.
Greg Stewart reports that corn planting ranges from 30 per cent completed in some parts of the south west to 95 per cent in eastern Ontario; provincially, 70 per cent of the intended acres are now planted. Switching to shorter season hybrids has been taking place in areas less the 3200 CHU. Some switching from corn to soybeans (approximately five per cent of intended corn acres) is also underway. Early planted corn (May 7) is at 2-3 leaf stage, some crusting and emergence issues are being reported on medium and heavy textured soils. Crust busting with rotary hoes, harrows, vertical tillage coulter units, etc., can improve conditions. Damage to corn is generally negligible unless shoot is broken below the soil deeper than 1.25 centimetres (one-half inch). Nitrogen is being applied to emerged corn. Guidelines for post-emerge UAN application: 1) UAN (fan nozzle) and herbicide – max. 2 leaf corn, 2) UAN (fan nozzle) no herbicide – max. 3 leaf corn, 3) UAN (streamer nozzle) – max. 6 leaf corn.
First-cut dairy haylage harvest is delayed and just starting in southern Ontario, but should be in full swing by June 2, according to Joel Bagg and Jack Kyle. With cooler spring weather, grass growth/maturity is more advanced relative to the alfalfa. Alfalfa is more than 10 days behind normal, while grasses are heading. First-cut yield potential is quite variable depending on the stand, but looks disappointing in some areas. In areas where soils are soft and wet, operating harvest equipment before the soil is firm enough can result in permanent wheel traffic damage to alfalfa crowns that impact the life of the stand. Although respiration, harvest, fermentation, storage and spoilage losses are largely invisible, they are very costly. Rapid wilting with wide swaths minimizes respiration losses. Reduce fermentation dry matter losses (shrink) by using a proven haylage inoculant. Fill, pack, cover and seal horizontal silos quickly to keep them anaerobic. Seeding sorghum and sorghum-sudangrass to supplement lower expected forage supplies is underway. These warm season annuals can yield well when managed with good agronomics and harvest management. (Forage Sorghum-Sudan Grass)
Orchardgrass is starting to head and should be grazed immediately to maintain quality and stimulate new leaf development, Bagg and Kyle report. Move to new paddocks when they have grazed half of the available forage. High stock densities assist with weed control. Monitor cattle on pasture, looking for problems such as grass tetany which can develop when animals have access to rapidly growing fresh grass.
Seeding continues to be delayed in many areas, reports Horst Bohner, although some growers have managed to finish. Most areas of the province still have considerable acreage unplanted. Many growers have not been able to plant any soybeans to date. There are no changes to management necessary for soybean seeded before June 10. After June 10, increasing seeding rates by 10 per cent can help achieve higher yields. Switching to narrow rows will also provide more yield potential with later planted fields. Target increased seeding rates to appropriate fields, generally those with lower yield potential. For fields with high yield potential that produce tall/lush plants, don’t to increase the seeding rates due to the increased potential for diseases. There is no reason to switch to lower maturity varieties at this date. Stick with the original plan despite the current date. For each three-week delay in planting, there is only a one-week delay in harvest maturity come fall. There is a 3:1 ratio in planting date to fall harvest maturity.