The factsheet, Sustainable Procurement in the Food Industry: An Introduction (Agdex 821-69) is now available through Alberta Agriculture and Forestry (AF). This factsheet follows an earlier workshop held for agriculture and food processors on sustainable procurement.
“The importance of sustainable procurement is growing and evolving into an integral business function in the food industry”, says Margurite Thiessen, value chain specialist, AF.
The new fact sheet offers another tool for the agriculture and food industry business. It provides an introduction to this practice and insights into challenges, benefits and best practices; as well as providing links to further resources. It joins AF’s free publications, a list of over 500 titles, available instantly online through the Agdex system (https://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/ipc4687).
Alberta residents can order hard copies of the free publication at no charge for individual use (non-classroom) by using the on-line order form (http://www1.agric.gov.ab.ca/$department/softdown.nsf/main?openform&type=AgFreePubs&page=download) or calling 780-427-0391 or faxing 780-422-8835.
On-line you can locate and download the fact sheet at Sustainable Procurement (http://www1.agric.gov.ab.ca/$Department/deptdocs.nsf/all/agdex16536) in the Agri-business section.
Winter wheat survival
Very low temperatures over Christmas and very little snow cover in the main winter wheat growing areas leads to an important question: how is winter wheat handling the temperature extremes?
Winter wheat seeded in September and October last fall grew then went dormant going into winter. For winter wheat to survive, its crown, which stores energy for spring regrowth, must develop prior to winter.
Winter wheat’s survival relies on keeping the crown healthy. It is normally very shallow, around two inches below the soil surface — which makes it susceptible to very cold temperatures, especially with no insulating snow cover.
Acclimation/Winter Hardiness
Winter wheat goes through an eight- to 12-week acclimation or “hardening off” process through fall and early winter. Acclimation begins when soil temperatures around the crown drop below 9 C. Winter soil temperatures at the crown are the critical measurement for winter survivability.
Winter hardiness is maximized by four to eight weeks of crown temperatures below 9 C. Winter wheat plants will acclimate faster with colder temperatures; however, a fall with a lot of temperature variability does not help the process.
Once acclimated, winter wheat usually maintains a high degree of cold hardiness as long as the crown remains frozen and the plant has an adequate energy supply. Prolonged periods of warming, such as those experienced with strong chinooks, can lead to a gradual loss of hardiness.
Survival
When soil temperatures fall below the plant’s minimum survival temperature, the crown tissue, and thereby the entire plant, dies. Temperatures just above the minimum survival temperature will cause immediate damage over time and reduce hardiness. For example, a Norstar wheat crown exposed to 50 hours of -18⁰C reduces the minimum survival temperature from -24 to -18 C, losing six degrees of cold hardiness. Fortunately, soil temperatures change slower than air temperatures.
Winter wheat reaches maximum winter hardiness in late November and December, with the most critical period of temperature stress occurring during prolonged cold spells in January and February. A lack of snow cover, which insulates the ground and provides a cold buffer, increases the chances of significant winterkill and cold damage.
Fertility can also affect winter survivability. Applying an adequate amount of phosphorus fertilizer with the seed will prevent a loss of winter survivability due to deficiency or excess.
Testing for Survivability
Early spring is the best time to assess how successfully winter wheat has survived. To test for winter survival in early spring, remove a few plants from the field on a warm day. Place the crowns in a moist, warm environment where they get exposed to light for at least part of the day. Don’t let the crowns dry out. Severely damaged crowns will turn brown while healthy tissue remains white. At room temperature, healthy crowns should produce new, white roots and green leaves in a few days. Don’t be too hasty to write off a crop that looks thin; some plants take longer to start growing in the spring.
Crops having a poor start in the previous fall are at greatest risk of winter damage. Keeping stubble up after harvest to maximize snow capture helps insulate the soil. The true sign of winter survivability is new root grown from the crown.