Agronomist Notes

A cool week has gone by and the rain gauge reads seven tenths at home and at the farm. Several hail storms have ripped through our area with estimated damage in the 20 to 90 percent range. I have a few heavily damaged canola fields where I’d like to try foliar boron to induce flowering. There is no data to support this theory so we’ll do some side by side trials.

On the canola insect front I’ve seen nothing significant. The cool wet weather has definitely impacted insect populations. Most of my sweeps have had 0-0.4 lygus per sweep, well below threshold. It’s still early for lygus bugs but it’s good to know populations before the end of flowering when they start to do damage. I’ve started my wheat midge checks around Three Hills and have found nothing yet.

This week we’ll discuss a range of topics- from soil compaction, integrated canola pest management, tips for scouting and spraying canola, stripe rust, fall desiccation and where we sit with crop maturity. Lastly, we’ll look at world crop weather news.

Crop Staging Area (Calgary to Drumheller to Three Hills)

Date Seeded:	April 23-31	May 1-7	May 8-15
Wheat	End of flowering	Flowering	Heads emerging
Canola	70% bloom	50% bloom	60% bloom
Barley	Heads emerged	Heads emerged	Heads emerging
Peas	Flowering	Flowering	Flowering

This Week in Scouting

July 15th is the cutoff date for most herbicide company’s product inquiries
Scout for wheat midge
Identify areas of uneven head emergence or maturity and document reasons why
Continue sclerotinia risk assessment in canola
Continue sweeping canola for insects

Agronomy

Stripe Rust Update: Nothing so far

For the last four years we’ve been inundated with stripe rust hammering CPS and winter wheat yields and to a lesser extent Hard Red Spring wheat. Thankfully, stripe rust has not arrived this year. In a recent trip to a field school at Lethbridge I asked local producers and agronomists if they had seen any and the word was no.

Typically, when the US winter wheat harvest begins, stripe rust spores are blown into the air during harvest and catch southern winds blowing north into Canada. I suspect the late US winter wheat harvest this year has slowed its spread. If stripe rust does arrive soon, many of our wheat crops in the heading to flowering stage are past the point where a fungicide would offer a yield benefit. SL

Steve’s Tips for Canola Insect Spraying and Scouting

1. Do not spray for cabbage seedpod weevils past 30% bloom. Why? Because the damage has already been done. Spraying should have occurred before 30% bloom which is the time weevils deposit their eggs inside the developing pods. Damage occurs in August when weevil larvae eat seeds then leave exit holes that cause premature shattering.
2. When spraying for lygus bugs, remember the economic threshold of 1 to 2 lygus per sweep begins at the end of flowering and not before.
3. Sweep inside the field and away from the headlands. Insect counts are always highest along the headlands where insects like lygus and weevils land first. I check one spot on the headland to see what insects have entered the field and then walk in to do my sweeps.   
4. You cannot count Diamondback Moth, Bertha Armyworm or Beet Webworms thresholds using a sweep net. Count these insects by the square metre or square foot and multiply by 10. SL

Revised Canola Insect Thresholds

Due to higher commodity prices, a committee of provincial entomologists has put together revised thresholds for several insects. A link outlining those revisions is available at:
http://www.canola-council.org/uploads/Canola_Insect_Thresholds_Update_Summer_2008.pdf

Integrated Pest Management: Canola

Today’s economic threshold for lygus bugs in canola is 1 per sweep at $14 canola and $13 application costs. However, in my quest to reduce costs and provide a sustainable approach to farming, I won’t be using the lowered thresholds again this year. My strategy will be to continue using the 3 to 4 per sweep threshold for lygus bugs and allow the subsequent buildup of beneficial insects by reducing the amount of insecticide we use.

In many areas I’ve seen the same producers spray every year because lygus bug levels are extremely high. I believe the reason is due to the unfortunate removal of the beneficial predator insects. Given the opportunity, predator insect populations will increase in response to pest populations, striking nature’s delicate balance. A program that involves the yearly application of insecticides keeps us dependent on insecticides, which is not the goal of any sustainable and profitable farming system in my opinion. SL

Crop Maturity: Where Do We Sit?

Crop maturity is directly affected by the number of growing degree days we receive each year. Growing degree days is simply the calculation of the highest daily temperature plus the lowest daily temperature divided by two and subtracting five (Ex: 200C + 100C ÷ 2 - 5 = 10 GGD). You subtract five because it is assumed that plant growth does not occur at less than five degrees Celsius.

Growing Degree Days from May 1st to July 12th:
2008: 693
2007: 728
2006: 828
2005: 692
2004: 607
5-year average: 709

To date we are 2.3% below the five-year average for crop maturity and on track for the second coldest year since 2004. Unfortunately, many crops were seeded between May 15th and June 1st leaving them vulnerable to fall frosts. Let’s hope we make up some ground in late July and August. SL

Prepare For a Desiccation Program This Fall

As I drive around the countryside looking at head emergence and flowering I notice many fields are experiencing uneven maturity. I would say 30% of the 7,500 canola acres I manage are two-staged. For example, 40% of the plants are in 30% bloom with the other 60% just beginning to bloom. This has made it very difficult to time sclerotinia fungicide applications. What’s more, this year’s swath and harvest timing may be even more difficult.

I would plan for a glyphosate or swath desiccation program in cereals and canola given the late and uneven maturity of our crops. If the heat turns on then it may not be an issue. However, I hear glyphosate prices may rise 23% if they haven’t already. Securing your glyphosate now at a lower price before everyone scrambles for it this fall will pay dividends. Take a look at your crop maturity and identify whether you’re fields may benefit from a fall desiccation program. Waiting for crops to mature when we know harvest may not begin until September leaves us at risk for reduced quality. It’s food for thought. SL

Yield Loss from Air Cart Compaction

Watching the effects of compaction on crop maturity in wheel tracks has me wondering if we should be using duals on larger 400+ bushel air carts. The popular move towards larger air tanks has caused greater concern for wheel track compaction and it’s been a particular problem for the last two years due to wet springs. In 2007, many producers experienced a 10 to 15-day delay in crop maturity from the compaction caused by the air cart. We may see the same situation this year. So, let’s look at the return on investment if we choose to put duals on the air cart.

Steve’s Quick Math: The cost of putting duals on a new JD 1910 430bu tank is an extra $8,000. Dual back tires will give you another 28 inches of footprint verses a single tire. That works out to 4.6% less compaction potential on a 50 foot drill. On a 160 acre field that’s 7.36 acres with the potential to lose 5% yield on a 50 bushel wheat crop. That works out to 18.4 bushels in yield loss per 160 acres. A 4,000 acre farm would lose 460 bushels per year x $7.00/bu equals $3,220 in yield loss each year. The $8,000 investment would be paid off in two and a half years and yield, quality, fuel efficiency and harvestability would improve.

Soil compaction can be another significant factor to limiting yields and quality. It certainly isn’t a topic that is addressed very often yet we see the effects each year. This example targets the air cart as the problem but we know that many pieces of machinery travel across our fields each year. We could throw up our hands and say that’s just part of farming or we could actually look into each farming system (seeding, spraying, harvest) and see how we can improve yields and profitability. Increasing production and farm profitability is about making a large number of small changes. SL

Compaction articles: http://www.farmandranchguide.com/articles/2006/06/23/ag_news/production_news/prod14.txt
http://www.lgseeds.com/lg_tech/tech_67.asp

Market News

United States: In the West, scattered showers and thunderstorms associated with the southwestern monsoon continue throughout Arizona and New Mexico. Drier, locally hot weather persists elsewhere, accelerating crop and pasture development. On the Plains, drier weather is developing in western sections of Oklahoma and Texas. Mostly dry weather dominates the northern and central High Plains, but isolated showers linger toward the east. In the Corn Belt, stormy weather is advancing across the upper Midwest, and scattered showers have returned to the middle Mississippi Valley, but another day of drier, generally sunny weather is benefiting corn and soybeans in the Ohio Valley. In the South, showers and thunderstorms are expected today from the Delta to Florida, bringing localized relief from summer warmth and dryness to summer crops and pastures. Drier conditions prevail in recently wet areas of southern Texas.

Europe: In northeastern Europe, showers improve moisture supplies for filling winter wheat and rapeseed. In central Europe, rain benefits filling winter grains and vegetative to reproductive summer crops. Dry, hot weather in southern Europe favors winter grain maturation and early harvesting.

Former Soviet Union: In Ukraine, showers ease short-term dryness in western and northern areas, while mostly dry weather in southern and eastern areas helps winter grain harvesting but limits moisture for spring-sown crops. In Russia, showers benefit spring-sown crops but slow winter grain harvesting in the Southern District. In Kazakhstan, timely rain benefits spring grains, in or nearing reproduction.

East Asia: Widespread showers in Manchuria and the North China Plain favor summer crops.

Southeast Asia: Monsoon showers maintain favorable soil moisture for rice and corn in Thailand. Wet fields continue in the Philippines, providing unfavorable growing conditions for rice and corn.

South Asia: Locally heavy rain in northern India maintains abundant soil moisture for recently planted summer crops but causes additional flooding and fieldwork delays. Lighter showers favor soybeans in central India.
Australia: Warm, dry weather continues in Queensland and most of New South Wales, further reducing moisture supplies and slowing winter wheat development. Scattered, light showers fall across southeastern and western Australia, but more rain would be welcomed to aid winter grain germination, emergence, and establishment.

South America: Drought-related planting delays continue in wheat areas of central Argentina. In Brazil, conditions favor winter wheat development.

Canada: Warmer weather aids development of spring grains and oilseeds, especially in western growing areas.

Mexico: Timely rain falls across the southern plateau corn belt.