Zadoks is a scale, rather than a day count. So if the heads are all present at Zadok 77, that means at 77% of the growth cycle.
Here's a study that shows a 50% head count at 130 days and 150 days for two varieties of winter wheat.
http://grainsearch.net.au/PDF/WheatVarietyTrialInverleigh2009.pdf
The soil for GPP's trial came from a Victorian wheat farm. We aren't told the residual N status.
I wasn't querying the germination or survival rates, but the heads per plant of the surviving plants, an average of 0.8 for the control.
cfp, why wouldn't running a trial in the summer involving a late flowering winter wheat and only reporting the results at 79 days raise questions? Publishing the whole trial results from Monash should answer a lot of them.
