May 14, 2014

Agronomist Notes

Hello Reader

We've had a stretch of good weather over the last 5 days and are now roughly 30-40% done planting. After all the rumours of fertilizer shortages and logistical issues, I haven't heard one peep about delayed products or delivery.

Mitch and I are nearing 80% done planting so forgive my tardiness over the last few weeks getting the newsletter out. We should be done by this weekend. Hard to believe this is our fifth year in controlled traffic farming.

This week while we’re all in the field, I’ll keep the newsletter brief. First, I’ll outline a tool to help you increase maturity. Next, I'll provide you the facts on seed to soil contact. I'll finish with how late we can seed wheat and canola to reduce the risk of fall frost. We'll finish with technical grain market news.

Have a great week.

Photo: The ole' Steiger on singles mastering 16-inch tall stubble where we inter-rowed peas into this wheat stubble. The stubble polished up the undercarriage nicely!

Agronomy

Bumping seeding rates to increase maturity

One of our biggest risks to profitability in wheat production is an early frost in late August or early September. Early frosts can significantly reduce wheat yield and quality or both. With the cool spring so far, it might be wise to begin increasing seeding rates in wheat by 10% after May 15th. Research has shown that seeding rates have the largest impact on tiller numbers. The higher the number of tillers, the more you will delay maturity. You see, on average, it takes roughly 3 to 4 days for a new leaf or tiller to emerge under average temperatures. Cooler weather can extend that period to 5 or 8 days thereby increasing your chance of delayed maturity and frost risk. Thankfully, we can do something about it. Here is what I like to recommend:

Increase seeding rates by 10% after May 15th. So, for those who normally target 24 plants/ ft2, you may want to increase your target to 27 plants/ ft2. Those of you who target 28 plants/ ft2 can increase that target to 31 plants/ ft2. With a cool start to the season, a great way to play catch up is to increase seeding rates. The additional cost in seed and treatment can generate big returns. SL

Seed to soil contact

Seed to soil contact has been touted as an important method of improving seed germination. Drill designs have emphasized seed to soil contact and soil moisture as a critical part of rapid germination. A study published in the Agronomy Journal compared germination with and without seed to soil contact over a temperature range from 3 to 28°C. The wheat seed was either provided with good seed to soil contact or separated from soil by fiberglass cloth. The results showed that vapor transport may be the most important mechanism for germination and that water transport via seed to soil contact provides little contribution.

This doesn’t mean that seed to soil contact isn’t important; it means that seed to soil contact provides a separate benefit aside from germination. Proper seed to soil contact is reflective of openers and packers placing the seed at even depths in row and across the drill and through proper separation away from fertilizer. This allows seeds to emerge evenly and safely away from harmful fertilizer bands. The end result is improved seedling emergence, which is why seed to soil contact was first thought to improve seed germination.

Source: Agronomy Journal , PAMI Report

How late can I seed wheat and canola?

Many producers are faced with the decision whether to continue planting canola and wheat or switch to barley. This is a difficult question to answer but the best we can do is estimate the days to maturity and understand the risk of planting wheat and canola into late May. The biggest risk in our area is fall frost and the damage it does to grade and yield. With that, the best we can do is look at our average fall frost and subtract the days to maturity or swathing to discover our drop dead seeding date for wheat and canola.

The most common wheat varieties in my area are CDC Go and AC Harvest, which are pegged at a 110-day growing season. I know the days to maturity differ on each farm depending on climate, agronomy and management but we’ll use this as a starting point. The days to swathing for most medium maturing canola varieties fall in the 105 to 110-day range.

The average date of the first fall frost throughout most of Alberta is September 11th to 20th (see map here). The first fall frost in areas north of Edmonton, Lloydminister and West of Calgary along the foothills is September 1st to 10th and around Medicine Hat is after September 20th. If you count back 110 days from September 11th for example, that would make May 26th the latest date for canola and wheat. Any later than May 26th and you’re looking at the potential for frost damage. If you have plenty of canola of wheat planted already, perhaps you can take the risk of a downgrade and blend these acres off with the rest of your early seeded wheat and canola. SL

Source