Drought hits Waikato maize yields
The tonnage from this year's maize silage harvest on Waikato farms has been hugely variable as a result of the drought.
Yields have varied from as low as 14 tonnes per hectare on lighter soils to up to 26 tonnes on heavier and good peat soils.
Waikato Federated Farmers Grain and Seed Industry Group chairman John Hodge said it had been a tough harvest.
"The metabolic energy is down so people will be disappointed."
The poorer yields seemed to be only in the Waikato. Further south in Te Kuiti and east to Whakatane there had been some excellent crops, he said.
"The drought has certainly affected the maize silage yields."
Crops had dried down quickly as a result of the dry weather while there were patches within the crop that were still green.
This made it difficult to decide when to harvest maize silage.
Hodge said farmers had to estimate what percentage of the crop was dry and what was still wet.
Drought-stressed crops with few kernels can also have high nitrate levels.
If green chop was urgently required for feeding hungry animals then get a vet to test a sample for its nitrate levels before feeding, he said.
The maize grain harvest, which was just about to start, faced a similar problem.
"The major concern this year will be the quality of grain on the cobs. Because of the lack of moisture some plants in patches died before the grain reached black layer."
This is when the grains reach maturity and do not fill any more.
A black spot appears on the base of each grain, indicating that the milk or moisture had dried out of each grain. After combine harvesting, the maize is dried down to 14 per cent moisture to store it and to stop it from sprouting in the silos.
If it has not reached black layer before harvest, it will shrink during the drying process and become poorer in quality with a lower feed value. Longer maturity varieties planted late are more susceptible to the quality problem, especially this year with the lack of rain.
"I get reports from a wide maize growing area of both North and South Islands of New Zealand. Last year the drought was widespread but this time it is in patches. Whangarei, Bay of Plenty, the centre of the North Island and most of the South Island have received significant rainfall so their crops are looking really good."
Last season's maize grain was in very short supply with bulk price per tonne above $500. A lot of dairy herds are being dried off so the demand for meal should drop off with animals going on to a maintenance diet, Hodge said.
Maize grain merchants are waiting for the new season's harvest to start coming in.