'Mad Monday' freeze sends shiver through grain areas

The unseasonal frosts were particularly bad on the South-West Slopes and in central areas and up to the Gunnedah region. There was an anecdotal report of a farmer losing his whole barley crop near Gunnedah.

On the bright side, many farmers reported that the Monday frost came more towards sunrise, lasted about three hours and was less frequent than originally expected after a horror 'three day run' was feared. Reports have come in to agronomists from the Griffith to Lake Cargelligo area of one to two frost events.

Monday morning was by far the worst time (see graphic) and farmers have been urged to inspect crops near creeks and river and low lying areas first before heading to higher country to inspect developing heads.

Peter Dowling, Euabalong, said the frost had come on about 4am on Monday morning and lasted about three hours. He felt the crops were quite resilient to the event.

Paul Connell, Elders Riverina, said initial fears were for substantial damage to crop yields. The frosts came at a damaging time in the grainforming cycle in its watery state.

Paul McCaskie, Wyrra, West Wyalong, said there were no visible frosts in his area, but seven to 10 days would tell the story after Monday. "We were pretty concerned, most of the cereals were well and truly flowering, but from what I can see I think we have escaped it. There might be some spikelet damage, but I'm not expecting any widespread damage." After 20-30mm in the area in September, it will help crops cope.

This year the McCaskies had planted 2500ha of wheat, 400ha of canola, 160ha of barley and 280ha of vetch. "We are very happy with how they've progressed. There has been some waterlogging damage, but we'll make up for that in other parts of the farm."

Local Land Services Central West has put some frost advice to farmers in its newsletter this week.

Callen Thompson, Mixed Farming Officer and Rohan Leach, Regional Agricultural Landcare Facilitator write that cereals are most susceptible to frosts between ear emergence and grain-fill while canola and legumes are susceptible whilst they are flowering.

"After a frost event farmers should aim to inspect their crops 7-10 days later for easy identification. Look in the most susceptible parts of the landscape such as the lower parts of the landscape or paddocks nearby rivers and creeks," they said

"If the crop is damaged here proceed to higher ground and reassess, stopping every 10-20 paces across the paddock to assess frosting.

"Stem frost can occur in cereals if the head has not emerged from the boot. To check that the developing head has not been damaged, you will need to carefully dissect the plant from the top down to find the head of the plant inside the leaf sheaths. If the crop has flowered, open the florets to check if the grain is developing. If you are worried you cannot identify accurately it is a good idea to tag a few plants with tape and return a week later to determine if head/grain development and grain filling is continuing.

"To calculate the best option financially, we need to estimate grain yield, dry matter yield and know the cost of production and commodity prices. When assessing yields, it is important to go to an area that is representative of the paddock. If there are areas of the paddock that are significantly higher or lower yielding and it is possible to treat them differently, it may be wise to measure them separately. As with all measurements we do in our cropping systems, the more samples you take, the more accurate your results will be with at least ten samples advised.

"As mentioned, find a representative area of the paddock. Measure out a metre of row, then count the number of heads and work out average grains per head. Don't count heads that are significantly smaller and will not make grain. Within the meter row count the number of grains on ten representative heads. You can count on one side of the head, then double that number.

"Then the formula is the number of grains per head, multiplied by the number of heads, multiplied by a factor of 0.027 to 0.029. That's to take account of grain size per thousand grains, and divided by the row spacing in centimetres. So, if it's a 25cm row spacing you'd obviously divide by 25."