Agronomist Notes

We’ve had a tremendous week of warm weather! Some of the lighter, drier ground will be planted this week just to get the drills and staff tuned up for go time next week should the weather hold. We’re definitely behind schedule but very few producers in our area are in panic mode. A lot of crop can be put in the ground quickly if the weather holds. Those of you who have fined tuned seeding efficiencies will be glad you did.

I’ve poked around a few fields and have noticed volunteer canola germinating as well as cleavers and dandelions. Soil temperatures are still hovering around zero degrees Celsius. Soil moisture is excellent but we’ll need more time for the ground to firm up and the rest of the frost to leave. I suspect we’ll be full on by the end of next week. Heads down chin straps on, but safety first, of course.

In this week’s issue of Beyond Agronomy News, we’ll focus on pre-seed burn off, including herbicide options for 2011 and maximizing efficacy. I’ve also thrown in a few tricks on using residual herbicides when weed growth is next to nil at seeding time. We’ll finish with fundamental and technical grain market news.

Agronomy

Maximizing pre-seed burn-off performance

We certainly have quite a number of choices when it comes to pre-seed burn-off options in the spring. From experience we know that a well timed pre-seed burn-off can buy us time in season, reduce early season weed competition and improve crop performance. At first glance it looks rather simple, but there are a few things to consider to enhance herbicide performance:

• Cropping rotation for the current year and in some instances the following year if you are concerned with soil quality and extreme moisture deficit conditions. Take a closer look at the following:
  • Organic matter %
  • Texture (% sand, silt and clay)
  • pH
  • In season rainfall
• Water quality may reduce herbicide efficacy of some herbicides, mainly glyphosate, 2,4-D and MCPA Amine formulations and CleanStart. Always have your water tested before the beginning of each spray season.
  • Bicarbonates >400 ppm
  • Hard Water >350 ppm
  • Suspended solids and organic particles (dirty water)
  • pH values <2.5 and > 8.0
• Timing pre-seed application and weed removal. It really depends on what crop and what weeds you are going after. Annual weeds are less of an issue but winter annuals, biennials and perennials may need to be addressed more carefully.
  • Pre-seed – 1-3 days prior to seeding.
  • Post-seed – 1-3 days after seeding prior to emergence.
• Water volume and application rates. At the end of the day, quite often it’s all about coverage and hitting your target. This is even more of an issue at spring burn off because many of the seedlings are very small. Generally higher water volumes give better coverage. Are you spraying a systemic product or contact herbicide? Typically the rate range is 5 to 10 gal/ac. The decision is yours on how much water you want to haul.
• Rotate your herbicide groups and modes of action. For most of us, the Group 2 products just seem to be a natural fit for most of the weed species we are dealing with. If you are using a Group 2 in your pre-seed, plan to change it up in crop with multiple modes of action, such as Group 4, 6, 27. Here are the pre-seed groups commonly used:
  • Group 2 – Express, Express Pro, PrePass(A),
  • Group 4 – Banvel, 2,4-D, MCPA
  • Group 6 – bromoxynil/ Pardner, Buctril M
  • Group 9 – glyphosate
  • Group 14 – CleanStart (AIM), Authority, Heat
• Glyphosate products and comparing rates. In the last couple of years we have been exposed to an overwhelming number of glyphosate products in Western Canada (more than 25 product labels). There are subtle differences between all of them, although the common denominator is the REL (Roundup Equivalent Litre or Relative Equivalent Litre). The REL lets us compare apples to apples, regardless of the formulation, active ingredient concentration and packaging size. The glyphosate products we purchase are available as 356g, 360g, 450g, 480g, 500g and 540g/ai. All we want to know and compare is what it costs and how much do we need at a rate of 0.5 REL or 1.0 REL.

Pre-Seed herbicide options for 2011

Let’s run through the list of the most common products and tank mix combinations. We won’t highlight all the combinations or all the weeds on the labels, but rather focus on the more common resolutions. With all the combinations listed below, pretty much each one can be topped up to 1.0 REL of glyphosate for enhanced performance.

Glyphosate – 0.5 REL - $1.25/ac and 1.0 REL - $2.50/ac
Crops: all crops
Timing:  pre-seed or post-seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, non-RR volunteer canola
Improved performance at 1.0 REL:  rosettes > 6 inches, shepherds’ purse (bolting), larger annual weeds, winter annual or biennials, kochia, quackgrass, dandelion, narrow-leaved hawk’s beard, and many others.

Glyphosate 1.0 REL plus 2,4-D Amine or Ester 0.2 l/ac (0.2 to 0.68 l/ac)  - $4.58/ac
Crops: wheat, barley, rye
Timing:  pre-seed or post-seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola (up to 4 leaf). Improved performance for many additional broadleaf weeds.

Glyphosate 1.0 REL plus MCPA Amine or Ester 0.2 l/ac (0.2 to 0.5 l/ac) - $4.86/ac
Crops: wheat, barley, canary seed, corn, flax, forage grasses, oats, rye
Timing:  pre-seed or post-seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola (up to 4 leaf). Improved performance for many additional broadleaf weeds.

Glyphosate 1.0 REL plus Buctril M @ 0.2 l/ac (0.2 to 0.4 l/ac) - $5.63/ac
Crops: wheat, barley, canary seed, corn, flax, forage grasses, oats, rye
Timing:  pre-seed or post seed/prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola (up to 4 leaf). Improved performance for many additional broad leaved weeds including wild buckwheat and scentless chamomile

Glyphosate 1.0 REL plus Pardner @ 0.2 l/ac (0.2 to 0.5 l/ac) - $6.13/ac
Crops: wheat, barley, canary seed, corn, flax, forage grasses, oats, rye
Timing:  pre-seed or post seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola (up to 4 leaf). Improved performance for many additional broadleaf weeds including wild buckwheat and scentless chamomile.

CleanStart – 0.5 REL glyphosate plus carfentrazone - $6.75/ac
Crops: all crops
Timing:  pre-seed or post seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola (up to 2 leaf). Improved performance by increasing water rates up to 10 gal/ac to ensure better coverage.

PrePass – 0.5 REL glyphosate plus florasulam - $5.83/ac
Crops: wheat, barley, oats
Timing:  pre-seed or post seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, LL & RR volunteer canola. Limited control of Clearfield volunteer which has not emerged. Excellent control on cleavers, dandelions <6 inches, narrow-leaved hawk’s beard, wild buckwheat and stork’s bill. Residual control of 7-14 days.

Glyphosate 0.5 REL plus Express SG - $4.85/ac
Crops: wheat, barley, oats, canary seed, dry beans, peas, forage grasses, forage legumes
Timing:  pre-seed or post seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola. Excellent control of dandelions <6 inches, narrow-leaved hawk’s beard, wild buckwheat and white cockle suppression.

Glyphosate 0.5 REL plus Express Pro - $5.35/ac
Crops: wheat, barley
Timing: pre-seed or post seed/prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola.
Excellent control of dandelions <6 inches, narrow-leaved hawk’s beard, wild buckwheat, cleavers, stork’s bill, scentless chamomile, night flowering catchfly and suppression of white cockle and toadflax. Residual control of 7-14 days.

Glyphosate 0.5 REL plus Heat (10.5g) plus Merge (200 ml/ac) - $6.23/ac
Crops: wheat, barley, oats, canary seed, peas, corn, lentils, soybeans
Timing: pre-seed or post seed/prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola. Excellent for helping manage group 2 resistant weeds. Very quick and aggressive results.

Glyphosate 0.5 REL plus Heat (28.1g) plus Merge (200 ml/ac) - $12.68/ac
Crops: wheat, barley, oats, canary seed, peas, corn
Timing: pre-seed or post seed/prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola. Residual control at the 30 acre rate for kochia, cleavers, wild buckwheat, red root pigweed, stinkweed, wild mustard, and volunteer canola.

Glyphosate 0.5 REL plus Authority (118 ml/ac) - $20.46 or
Glyphosate 0.5 REL plus Authority (95 ml/ac) - $16.62
Crops: chickpeas, peas, flax, summerfallow
Timing:  pre-seed or post seed/prior to emergence
Target Weeds: annual grasses, annual broadleaves, and all volunteer canola. Season long control of kochia, lambs quarters, redroot pigweed and wild buckwheat. Rates vary according to soil texture and organic matter. Requires moisture within 7-10 days for optimum activity. Re-cropping restrictions: 12 months for barley, wheat, corn, and alfalfa, 24 months for canola, 36 for lentils.

Glyphosate 0.5 REL plus Prepare (8.7g) - $8.73/ac
Crops: wheat (spring, no durum)
Timing: pre-seed or post seed/ prior to emergence
Target Weeds: annual grasses, annual broadleaves, all volunteer canola, wild oats, green foxtail, Japanese brome, downy brome, barnyard grass, foxtail barley. Residual control for wild oats and green foxtail. Let’s you get an early start on wild oat control.

Early season residual weed control strategies

It’s very common to have little to no weed growth in late-April or early-May when ground temperatures are cool. We all know the value of pre-seed burn down but struggle over spraying when it seems there are no weeds present. If you find yourself in this situation and want to control flushing weeds like volunteer canola or cleavers, here are two options:

1. Apply PrePass A (florasulam) alone at 40 ml/ac and leave out the PrePass B (glyphosate). If there aren’t any grassy or perennial weeds, I’ve had great success controlling flushing cleavers, volunteer canola, flixweed, shepherd’s-purse, narrow-leaved hawk’s beard, stinkweed and wild buckwheat. It’s amazing how many weeds germinate after the ground is disturbed at seeding and skipping the pre-burn is often regretted. The unused PrePass B can be saved and used on another field in the future.
 
2. Apply Express Pro at 7 g/ac with a surfactant like Agral 90 at 2L/1000L to give residual control of volunteer canola, seedling dandelions, flixweed, narrow-leafed hawk’s beard and wild buckwheat. I’ve had great success with this option and it’s more convenient than splitting a case of PrePass as suggested above. SL

Optimize pre-burn herbicide performance this spring

Pre-burn herbicide timing is the worst possible time of year to ask any product to perform well. Conditions in late-April and early-May are often cold, windy, and frosty with low daylight hours. This can lead to poor herbicide performance and many producers tend to increase their glyphosate rates to improve uptake. However, poor performance can be linked to poor water quality and not just weather conditions. The two most undetected problems associated with poor pre-burn herbicide performance are pH and hard water.

Did you know that on average, up to one third of your glyphosate and sulphonylurea (Express and Express Pro) can be tied up in the spray water before you even apply the herbicide? This is alarming, but the severity depends on how hard your water is. That being said, how many producers know how hard their water is? Here's the chemistry behind the problem: glyphosate and sulfonylurea molecules are negatively charged and are naturally attracted to positively charged cations like potassium, calcium, magnesium, zinc and sodium. Once the herbicide attaches to a cation, it becomes insoluble and can no longer be taken up by the plant.

The next hindrance to herbicide uptake is the pH of the spray water. High pH in the spray water can cause alkaline hydrolysis which breaks down the active ingredient in the herbicide. In high pH water, it may take only a few minutes to lose a significant amount of active ingredient. Unfortunately, most town and well water has a pH of 7 or above. To reduce the effects of alkaline hydrolysis, maintain a spray solution pH between 5 and 6.5.

There are a couple of ways to reduce water hardness and balance pH in your spray water. The first is by adding ammonium sulphate (AMS). The ammonium component of AMS is positively charged and competes against other cations to attach itself to glyphosate. The resulting ammonium-glyphosate molecule is easily absorbed into the plant because it sees it as a nitrogen source. The downside with AMS is that it only ties up calcium, leaving other cations like potassium, magnesium, iron and sodium to tie up glyphosate and sulphonylurea. Also, AMS has a limited acidifying effect and can only drop the pH down to 4.5 in the spray solution. Products like glyphosate cannot be tied up when the pH of the spray water reaches below 4.5.

To calculate how much AMS you need follow this formula:

Amount of AMS Liquid (8-0-0-9) (Litres per 100 gallons of water) = [0.009 × (ppm calcium) + 0.005 × (ppm sodium) + 0.002 × (ppm potassium) + 0.014 × (ppm magnesium)] × 1.2 (Conversion of US to Imp. gallons)

Another option is using a water conditioner like pHix by Omex and BB5 by NutriAg. These products contain negatively charged ions that bind to the cations which normally tie up glyphosate and sulphonylureas in the spray water. I prefer these products because they actively tie up the cations that cause hard water instead of trying to compete against them like AMS plus a lot less product is required. Second, conditioners often contain surfactants that help improve plant uptake by reducing the surface tension of the water droplet so it lays flat on the leaf surface. This provides more area for the herbicide to enter the plant. Last, conditioners like pHix and BB5 have pH adjusters which can take the spray solution pH down below 4, a level that chemically alters the ability for cations to bind to glyphosate or sulphoylureas. 

The cost of ammonium sulphate can run you $1 an acre or more and it doesn't tie up all the cations that attach themselves to glyphosate and sulphonylureas. A water conditioner like pHix costs around $0.50 acre while BB5 is between $0.50 and $1.50 depending on how hard you’re your water is. So, before you head out this spring, be sure to have your water tested so you're getting the most out of your herbicide dollar. The additional $0.50 acre could give you a 3:1 return on your investment and improve performance so you don't have to spend extra money on in-crop herbicides trying to kill the same weeds you targeted at pre-seed burn-off. SL

BB5: http://nutriag.com/products/bb5.html
pHix: http://www.engageagro.com/uploads/brochures/phix_brochure_english.pdf

Host your safety meeting now

With a later than normal spring, producers and their staff are going to feel pushed to work longer, harder and faster to get the crop in the ground in a timely manner. That brings the risk of pushing the envelope on safety much higher than other springs. With that, there a few things to keep in mind:

• Empower your staff to feel free to call you whenever they feel unsafe.
• Don’t assume that your staff think the same was you do so be patient and listen to your employees when they do have a concern.
• Everyone should know who to call in case of an emergency.  
• Injuries happen when you take shortcuts in performing routine tasks, work while mentally or physically fatigued, or fail to follow safety guidelines.

For a list of fact sheets on farm safety go to: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/aet10712#3