Producers are always evaluating their crop sequences and rotations seeking to maximize returns without jeopardizing future income through poor agronomic practices. Producers who are growing or want to grow special crops like canaryseed, coriander, hemp or quinoa lack this valuable information. The objectives of this research was to determine the best fit of special crops into crop sequences and to determine if optimum crop sequences change depending on the environment. A multi-location field study was initiated at Indian Head, Melfort, Saskatoon, and Swift Current to evaluate the impact of eight crop stubbles, wheat, oats, canola, pea, canaryseed, are seeded perpendicular to the strips in the first year.  After examining the results several conclusions can be reached including:

1. Of all the broadleaf crops in this study, coriander showed the clearest preference for being seeded into a cereal crop verses being seeded into a broad leaf crop.
2. In this study quinoa grain yield was supressed to very low levels. Several insect species at different points in the life cycle of the quinoa were impacting the growth, production and yield of quinoa.  The impact of these insect species was so large that it became difficult to determine any stubble effects. Research by Wist and Mori (2019) have shed significant light on this problem.  Their report should be carefully studied before new agronomic research on quinoa is undertaken in the future.
3. There was a small trend of pea grain yield being most consistent on oat and wheat stubble
4. Wheat, oat, canola, canaryseed and hemp were able to tolerate a wide range of crop stubbles
5. Oat, canola and coriander presented the biggest risk as volunteer plants in the next crop and a plan should be in place to deal with theses volunteers when seeding into these stubbles

When looking at the results of this study it must be remembered that the environmental conditions for moisture ranged from very dry to normal.  If there are crop sequencing impacts that only occur under wet conditions they would not be easily observed in this study.

Extension Messages:

Of all the broadleaf crops in this study, coriander through its grain yield showed the clearest preference for being seeded into a cereal crop verses being seeded into a broad leaf crop.

In this study quinoa production was difficult with grain yields often approaching zero. Several insect species at different points in the life cycle of the quinoa were impacting the growth, production and yield of quinoa.  The impact of these insect species was so large that it became difficult to determine any stubble effects. Before growing quinoa producers should have a plan for managing insects in this crop. Currently two dominant pests of quinoa have been identified, the goosefoot groundling moth, Scrobipalpa atriplicella (von Röslerstamm) (Lepidoptera: Gelechiidae), which attacks quinoa heads and secondarily invades stems and larvae from a stem-boring fly, Amauromyza karli, (Diptera: Agromyzidae), which begins by leaf-mining, then bores into stems and destroys the vascular tissue.

Wheat, oat, canola, canaryseed and hemp were able to tolerate a wide range of crop stubbles

Pea stubble appearing to provide a slight increase in the grain yield of wheat compared to the other seven crops.

Oat seeded into canaryseed stubble tended to have a higher probability of wild oat in the harvested sample than the other stubble crops. This highlights the risk of seeding oat into canaryseed stubble or any stubble in which wild oat control is less than optimal. The same risk exists when the order of the two crops is reversed and canaryseed is seeded into oat stubble

There was a small trend of pea grain yield being most consistent on oat and wheat stubble.

Oat, canola and coriander presented the biggest risk as volunteer plants in the next crop and a plan should be in place to deal with theses volunteers when seeding into these stubbles.