Harvesting and yield
Harvesting starts as early as September in Central Queensland and can be as late as December on the Eastern Downs. Harvesting can commence whenever the header is capable of giving a clean grain sample. This is usually when grain moisture is below 20%.
Where grain drying facilities are available, harvesting can start well before the crop dries down to the required 12.5% moisture and so reduce the time the crop has to stand at risk from weather damage in the field.
Pre-harvest spraying with glyphosate
Yields vary widely from season to season and with district. Long-term average yield in Queensland is approximately 1.2 t/ha, although paddock yields of 5 t/ha may be achieved with good conditions providing nutrition is adequate and the crop is free from disease.
Grain density standard is 75 kg/hL, although wheat often achieves 80 kg/hL.
Header settings
Yield (tonnes per hectare)
Yields vary widely from season to season and with district. Long-term average yield in Queensland is approximately 1.2 t/ha, although paddock yields of 5 t/ha may be achieved with good conditions providing nutrition is adequate and the crop is free from disease.
- Central Queensland dryland 2.0 t/ha
- Darling Downs northern 2.5 t/ha
- Central Queensland irrigated 5.0 t/ha
- Darling Downs western 1.5 t/ha
- Darling Downs central 3.0 t/ha
- South Burnett 1.5 t/ha
Effect of grain defects on end product quality
Black point
Frost damaged wheat
Excessive levels may result in specky semolina, discoloured bran, wheat germ and divide flours (pastry flour). End products are often visually unattractive, this is particularly the case with durum products (for example, pasta), APH and AH bread wheats.
Sprouting (low falling number)
Finished product is affected by high amylase levels present in the flour - causes key-holing in bread, fragile noodles, dark discoloured biscuits and cakes.
Frost damage
Can cause low falling number, reduced flour yield, increased grain hardness and poor baking performance - bread, biscuits and breakfast cereals.
Excess screenings
Reduced grain and flour yield (loss of profitability) has little effect on end-product quality (excluding excess screenings due to frost and heat stress damage). During the 2002 harvest, it was observed that a number of samples tested with high screenings had poor baking quality. This was attributed to heat stress damage during grain filling, which was also believed to be responsible for the high screenings.
Low density (test weight, kg/hL)
Reduced grain and flour yield (loss of profitability) has little effect on end product quality (excluding low density due to frost and heat stress damage).
Heat damage (due to drying at temperatures above 60°C)
Flour produced from this grain is of poor baking quality and baked products are often unsaleable.
