MULTI-SCALE EVALUATION OF LAND USE MANAGEMENT SYSTEMS IN THE UPPER MIDWEST
Location: Soil Management Research
Title: Industrial oilseed crops and ecosystem services: Pollinators
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: November 15, 2012
Publication Date: November 15, 2012
Citation: Forcella, F., Gesch, R.W. 2012. Industrial oilseed crops and ecosystem services: Pollinators [abstract]. The Association for the Advancement of Industrial Crops. p. 28.
Many industrial and specialty oilseed crops have showy flowers that are highly attractive to insect pollinators. Moreover, across the spectrum of species and cultivars that can be grown in frigid regions, such as Minnesota, floral phenology can be manipulated to vary from early spring (April) to late autumn (November). This time period corresponds to that for transient honey bees, which typically are shipped to California in November and return to Minnesota in April. Currently, honey bee colonies are sustained in April-May and September-October by artificial diets comprised largely of high-fructose corn syrup (for energy) and soy meal (for protein) because floral resources are unavailable at those times. About one-third of transient colonies are lost annually and another large proportion under-perform in terms of pollination efficiency while in California. Causal mechanisms are many, but apiarists agree that poor nutrition during critical phases of a colony’s life cycle (spring and autumn) has wide-ranging and over-riding effects.
Our goal was to examine a broad array of oilseed crops, each with known economic value, for their flexibility in floral phenology and pollinator attractiveness. Minnesota-hardy crops included winter camelina, pennycress, winter canola, spring camelina, spring canola, calendula, flax, borage, echium, sunflower, and cuphea. They were sown in 3 by 7.5 m plots in a RCB design near Morris, MN. Planting dates and harvesting methods were used to manipulate floral phenology of some species. Weekly observational surveys of insect visitors and floral abundance were conducted over two growing seasons.
Although some oilseed species clearly were more attractive to some pollinators (e.g., echium and honey bee) than others, in general the more flowers present the greater the abundance of pollinating insects regardless of season. In essence, if seasonal conditions (e.g., air temperatures) are conducive to anthesis, irrespective of crop species, insect pollinators (including honey bees) will be present, often en masse, to tap that highly valued resource. Future research will examine pollinator health as a consequence of wider seasonal availability of floral resources.