Agronomist Notes

Special thanks to those of you who took the time answer our short survey. I greatly appreciate all manner of comments; I consider our readers to be well informed and hold valuable opinions.

Let me fire off some input prices for you: The retail market has remained fairly quiet with glyphosate prices continuing to slide lower at $3.20 a litre for 540 g/L product. Nitrogen prices have remained flat after their last jump up into the $400 a tonne range. Mitch and I just had some sulphur fines floated on at $250 a tonne plus $7 an acre for application. I managed to find some seed peas for $9.00 a bushel for a client. I wonder, with lower nitrogen costs, perhaps seeded acreage in pulses (except lentils) may drop year over year.

This week, we’ll look at the use of green leaf area in canola and how optimizing it equals high yields. Next, I’ll pass along a brief outline on the seven indicators of farm financial health from Merle Good and Mark Muchka. Last, we’ll look at foliar nutrient uptake and summarize the key points to understanding nutrient uptake through the leaves. Last, we’ll finish with fundamental and technical grain market news. Have a great week. 

Agronomy  

Optimizing leaf area index is key to achieving high canola yields

One of the key drivers in canola yield is leaf area index or what’s commonly known as green area index (GAI). GAI is the ratio of green plant material that covers a square meter of land and has a direct influence on crop vigour, root development, moisture use efficiency, weed suppression, carbohydrate storage and nutrient transport. In a nutshell, obtaining optimum GAI’s can build bigger canola yields with less water and nutrients. 

I had a chance to discuss the use of green area index measurements with Nick Ward, farmer and Nuffield Scholar from Linconshire, UK. Nick measures GAI in his canola to calculate nitrogen uptake and application rates in order to achieve optimum GAI and yield. I had Nick explain how UK producers use green area index to measure nitrogen uptake and calculate nitrogen application rates:

Measuring Green Area Index

• To quantify the amount of nitrogen taken up by the crop prior to bolting, a 1 square metre quadrant is placed in a representative area of crop. The entire green mass (stems and leaves) on this area is cut off at ground level and weighed (including dead leaves). Alternatively you can take a picture of 1 square metre of area standing above the crop and insert it into the BASF GAI online measurement tool [ http://www.totaloilseedcare.co.uk/canopy-management/GAI/index.html ]
• The weight of the green mass (stems and leaves) is measured in kilograms and multiplied by a factor of 0.8. This will give you a Green Area Index number. For example, 1 kg of green mass from 1 square metre would equate to a GAI of 0.8. (1kg × 0.8 = 0.8 GAI) or (0.750kg × 0.8 = 0.6 GAI) 
• Pictures of GAI examples.  [http://www.hgca.com/content.output/852/852/Resources/Tools/Green%20Area%20Index%20Tool.mspx ]

Calculating nitrogen uptake and N application rate

• It is assumed that each GAI of 1 contains 50kg/ha of N within the crop. If you want to convert kg/ha to lb/ac, simply multiply kg/ha by 0.893. For example, 50 kg/ha × 0.893 = 45 lb/ac of N within the crop. 
• Now, multiply your GAI × 50 kg/ha to calculate the amount of nitrogen in the crop. For example: 0.75 GAI × 50 kg/ha = 37.5 kg/ha N within the crop or 33.5 lb/ac N
• Next, the optimum sized canopy at full growth (bolting) has a GAI of 3.5. We need to build the crop canopy up to a target GAI of 3.5. Example: 3.5 - 0.75 = 2.75 GAI
• To calculate the nitrogen necessary to build an additional GAI of 2.75 we need to multiply 2.75 GAI × 50 kg/ha. For example: 2.75 GAI × 50 kg/ha = 137.5 kg/ha N or 123 lb/ac N
• Therefore, the crop needs 123 lbs/N/ac to reach its optimum canopy size and yield potential.

In Canada, a GAI of 4 is considered optimum for the crop canopy to intercept about 90% of the incoming solar radiation. (The picture above has a GAI of 1.8 to show you an example.) The larger the leaf area the crop can expose to the sun, the more dry matter the crop can produce per day. The more dry matter a crop can produce, the higher the yield potential. I’d like to run some numbers but instead, I’ll challenge you to start measuring GAIs in 2010. Start questioning what it would take to produce a GAI of 4 in your cropping system. Is it a change in row spacing, opener width, fertility program, nutrient placement, seeding rate, fungicide or variety? Let this be the beginning of a new way of measuring yield potential in canola.
 
Source: Nick Ward, Lincolnshire, England
Canopy photo source: GRDC

Top seven indicators of farm financial health

I haven’t touched on farm economics in while so I thought I’d include a quick summary of the top seven indicators of farm financial health. My job focuses on production and generating the highest return possible for the inputs we apply. However, generating the highest return on capital is equally or probably exceedingly important to the financial health of your farm. With that, the following seven indicators are meant to be a simple way to take a financial health 'snap shot' of your farm:

• Operating loan less than 50% of current value of unsold inventory
• Operating expenses less than 65% gross revenue (averaged over past four years)
• Net Revenue greater than 2x cash rent
• Machinery investment owned less than 2x gross revenue per acre (averaged over past five years)
• Machinery leases less than 15% of gross revenue
• Less than 20% total income from government programs
• Net Income > 20% gross (excluding government programs)

Indicators supplied by Mark Muchka and Merle Good of Alberta Agriculture. If you have any questions, please feel free to contact them at:

Mark Muchka
Business Strategist, Alberta Agriculture and Rural Development
Phone: 403-948-8504

Merle Good
Provincial Tax Specialist, Alberta Agriculture and Rural Development
Phone: 403-556-4237

Understanding foliar nutrient uptake for optimization

A lot has yet to be learned about the proper use of foliar nutrient programs with respect to plant uptake. In this article I’ll provide a number of tips to help you generate a better return on your foliar nutrient program just by understanding how foliar nutrients work and how to increase uptake efficiency.

Tips and facts on foliar nutrient uptake:

• Increasing the amount of time a leaf has to absorb foliar applied micronutrients before drying occurs is paramount to maximum absorption or nutrient uptake.
• Nutrients are only absorbed while the spray is wet on the leaf!
• Foliar micronutrient applications should be applied in early morning or late evening when humidity or dew levels are high to increase the length of leaf wetness and absorption potential.
• How many people apply foliar micronutrients at herbicide timing and spray in the middle of the day? Stop! You’re wasting your money if humidity levels are low and windy conditions are drying leaf surfaces quickly. If there is no rain in sight, save the herbicide/micronutrient applications until evening. 
• The application timing of macronutrients like nitrogen, phosphorus and potassium are opposite to micronutrients. Apply macros during the warmer, drier part of the day to help leaves dry quicker and avoid leaf burn or phytotoxicity.
• Macronutrients like N,P,K,S and Ca should only be a minor supplement to your soil fertility program. Leaves simply cannot absorb enough macronutrients to sustain optimum plant yield.
• Substantial research indicates that adding urea or potassium nitrate to liquid spray solutions improves the foliar absorption of micronutrients. 
• Try to reach both the upper and lower leaf surfaces with spray solution where possible through higher water volumes or dual spray nozzles.
• Use only chelated micronutrients. The chelation process forms an inorganic coating around the micronutrient which allows the nutrient to penetrate the waxy leaf surface. Once in the leaf, the chelate releases the nutrient so that it can be used by the plant.
• Remember, stomata must be open to allow nutrients to enter the plant. Stresses like drought, high temperatures, and frost prematurely close stomata and nutrient entry points.
• Try to maintain a spray solution pH below 6. The lower the pH of the spray solution, the faster uptake through the leaf.

There are a number of foliar micronutrient products on the market like Nexus, Stoller, Omex, UAP, Phosyn and NutriAg to name a few. Foliar nutrient programs do have a fit, just be sure to do everything you can to sure ensure optimum uptake by following the simple tips mentioned above. If you don’t, you’re only throwing money on the ground. SL

Market News

Technical Analysis

Canola: May futures. The short and long term trends are down. More lows possible.
HRS Wheat: May futures. The long and short term trends are down. Further declines are likely.
Corn: May futures. The short and the long term trends are down. Further declines are likely.
Soybeans: May futures. Short term trend is up and long term trend is down. Look for choppy market ahead.
Canadian Dollar: June futures. Long and short term trends are up. Look for choppy market ahead.
US Dollar Index: June futures. Short term trend is up and the long term trend is down.
Crude Oil: March futures. Long term trend is up. Short term trend is down.