Synopsis: Rain has been welcome especially further south, where it was very dry. Up to one inch of rain was reported. Hopefully, all the dry areas receive rain this week. Spraying will start in earnest as soon as the rain stops. Further north things are wet and not all field work is complete. Some severe ponding and significant soil erosion in hardest hit areas (Alliston, Wallenstein, others). Frost damage is variable across the province with 3 to 4 nights of frost (Thursday-Sunday). Up to 40% damage in tomatoes, a little frozen tobacco, and strawberries and blueberries would be at risk. Most of the corn was small enough that the growing point was still below ground and the majority of soybeans were not emerged. Most wheat was not advanced enough to be of concern, but the odd early field is at risk.Less than 10% of edibles have been planted.
Soybeans: 95% planted, although some areas still have considerable acreage to seed. The ground was very dry in some areas so drills were not able to penetrate into moisture, so seed ended up in dry ground. Rain this week will make a considerable difference in plant stands. Consensus was that it did not get cold enough to kill emerged soybeans in this area but more advanced fields further south where it was dry did have plant death. Areas within the field with residue suffered more damage. Plants damaged below the cotyledons by early-season frost will not recover. If the top growing point is destroyed but not the stem portion below, the plant will send out new shoots from the base of the leaves or cotyledons. It usually takes 3-5 days to see if new growth will emerge. Since temperatures are going to be over 25 C by the end of the week it will be obvious which plants survived, very soon. Soybeans are surprisingly frost resilient and stood up well. If the plants survive there is no yield loss associated with early season frost unless it has substantially decreased the plant stand. Growers are encouraged to wait on replanting until its clear how much damage has been done. Soybeans can tolerate -2.4 C for up to 4 hours before they are destroyed. Every year somewhere there is a virgin soybean field where the innoculant is forgotten. This years “winner” is Peter Johnson. The only answer is nitrogen. While the official recommendation is 50 pounds N/ac, a field with good yield potential will likely respond to at least 100 pounds N.
Corn: A lot of the corn looked very tough after the frost but it has started to improve over the last 24 hours. A little bit of corn on muck that may be frozen at the growing point. There is no need to wait to spray glyphosate because of the frost damage, or other products with excellent crop safety. Since there is very little healthy plant tissue almost no chemical will be able to enter the plant if spraying takes place now. It’s suggested to wait 2-3 days after a frost before spraying some “hotter” products (dicamba, group 2 products, etc). Remember to count frozen leaves when staging corn for herbicide applications. Even though leaves have been lost the physiological maturity of the plant will be similar to a plant that did not suffer from the frost. There was some discussion if corn damaged from frost is at increased risk of disease. There may be a slight increase in smut but experience has shown this corn will be fine. There is no real reason to expect a higher yield response to fungicide applications because of this early frost. DO NOT clip frozen corn: clipping is merely cosmetic and does not give the corn a better chance of recovery from frost damage.
Nitrate Survey: The annual soil pre side dress nitrogen survey will take place next week (June 3-4). Results will be posted as soon as they come back from the lab. It seems that the nitrogen kick from manure is slow this year.
Wheat: Wheat is heading in Essex. Freezing temperatures at pollination result in significant yield loss. Scout 5-7 days after frost and check for kernel development. Most of the crop will be fine. Much of the wheat looks good but there are a lot of yellow areas within fields even though they have received up to 120 lbs/acre of nitrogen. It is most likely sulphur deficiency causing this discolouration. Group survey says: 60% of the wheat gets a sulphur application (it should be even more judging from the way some fields look). Ammonium thiosulphate was scarce this spring and logistics are difficult. In a two pass nitrogen application system it may be easiest to apply dry sulphur in the first pass (eg. ammonium sulphate) and just use straight 28% for the second pass. It looks more like the spring of 2011 this year compared to last year. There was significantly more sulphur deficiency in 2011. Weather conditions may play a greater role in sulphur availability than we realize, and may be used in the future to predict sulphur responses. There is considerable tile run wheat in Lambton as well as “corn row syndrome” wheat. Fields with seed placed phosphorus look much better and show little corn row syndrome. It will be hard to stage variable wheat for fungicide application because of the variability of heading date within the field. Perfect staging is “Day 2”. “Day 0” occurs when 75% of the heads on the main stems are fully emerged. Most of the yield comes from leaf disease control: waiting for all heads to emerge in variable fields will mean earliest (best) wheat is at higher fusarium risk. Remind growers of the importance of tank clean out. Considerable damage is done every year from improper clean out: end cap clean out is essential. There is a great deal of leaf burn from fungicide/herbicide and late N applications. This is probably caused by cool, cloudy weather resulting in a thin cuticle on the leaf surface. Group survey says: 50 to 60% of wheat has a foliar fungicide applied.
Forages: First haylage harvested yielded very well (5 ton/acre). Good rye harvested was approaching 5 ton/acre. Rye does not like wet feet so not all stands are great. Keep an eye on newly seeded alfalfa after the frost. It’s very susceptible at the first trifoliate stage. Fortunately most of the newly seeded alfalfa was in the areas with less frost.
Agricorp: reports 260 damage reports so far on corn, soybeans, and wheat. Agricorp expects more calls to come in. Please call if you have damage. If reseeding is required an adjuster must first give the OK for coverage.
Diagnostic Days: July 3/4, Ridgetown Campus, University of Guelph.
Next Meeting: 7:00 am, Tuesday June 11th, Malibu Restaurant Thanks to Pat Feryn for chairing this week. Jim Morlock will be chair at the next meeting.