- There was a large difference in crop yield response to topping between both site and season.
- Topping later than two weeks after first flower may reduce seed yields.
- Seasonal flower production was similar from untopped and topped plots.
- There was no apparent relationship between the number of flowers produced and seed yield.
- Decreased yields may result from application of herbicides at later timings with the goal of reducing canopy size.
- Maximum yields can be expected when harvested at approximately seven weeks after peak flowering (2006/07 season).
- When expressed as thermal time, the time from peak flowering until optimum harvest date was 770 degree days. Thermal time is transferable between season and site and therefore allows for the use on this data in a practical sense year to year.