Milking longer with maize silage
This season's dry conditions have made one thing clear: not having enough feed on hand can bring your season to an early close.
Many farmers are experiencing lower stored feed reserves on hand and some are considering growing or increasing their on-farm maize crop grown.
It's not uncommon for farmers to be able to grow maize silage that yields 18-24 tDM/ha for around 25-35c/kgDM in the stack on paddocks that need renewing. Growing costs can be reduced even further by growing maize in an effluent paddock, which can significantly reduce (or in some cases eliminate) fertiliser input requirements.
This drops the cost of maize to 18-25 c/kgDM. That looks pretty attractive compared to buying in alternative feed sources that can range from 50-100 c/kgDM. However, this analysis only tells part of the story when growing maize on farm, and there are other considerations that can influence the return from your maize crop.
First, you need to ask whether the area you want to grow your crop on really needs renovating. The reason for this is that if the paddock is already high producing, the difference in the total extra drymatter production gained by growing maize will be less, increasing the cost per kgDM (Table 1).
Table 1: Value of maize grown on low vs high pasture producing paddocks
Poor Performing paddock | High performing paddock | ||
Maize yield | tDM/ha | 20 | 20 |
Less: Pasture production during maize cropping period | tDM/ha | 4 | 7 |
Equals: Total extra feed produced | tDM/ha | 16 | 13 |
Cost to grow and harvest maize silage1 | $/ha | 16 | 13 |
Cost of additional feed supplied |
Furthermore, you will have missed the long-term opportunity to increase pasture production by renovating the poorest performing paddocks on the farm.
Second, maize growing costs can be reduced significantly if you can grow it on highly fertile effluent paddocks.
Dairy effluent typically has higher concentrations of nitrogen and potassium, which maize can utilise to achieve maximum yields (12kg of N and 10kg of K per 1 tDM maize silage yield). With maize being a deep-rooted crop, it is perfectly suited to utilise this free source of nutrients and reduce the growing costs per kgDM (Table 2).
Table 2: Cost of maize grown on low v high fertility paddocks
Maize silage yield (tDM/ha in the stack) | |||||||
Yield | 16 | 18 | 20 | 22 | 24 | 26 | 28 |
Cost on low fertility paddocks ($kgDM)2 | $0.40 | $0.34 | $0.30 | $0.27 | $0.24 | $0.22 | $0.20 |
Cost on high fertility paddocks ($kgDM)2 | $0.29 | $0.25 | $0.22 | $0.20 | $0.18 | $0.16 | $0.15 |
Finally, while maize yield and costs are very important, so too is having flexibility around the timing of when you sow and harvest your maize crop.
Consider maize hybrids that suit your environment and the nature of your seasonal feed supply and demand requirements.
For example, being able to sow your crop three weeks later when pasture is growing at 64kg DM/ha/d, equates to 20 tDM of additional pasture silage from 15ha. Alternatively, being able to harvest three weeks earlier could help you to bridge any autumn shortfall of feed you might have normally expected. Talking to your local Pioneer representative will help you establish the best hybrid option for your location and on-farm requirements on farm.
Wade Bell is Genetic Technologies farm systems manager. Contact him at This email address is being protected from spambots. You need JavaScript enabled to view it.
Among this year’s Primary Industry NZ (PINZ) Awards finalists are a Southlander who created edible bale netting and rural New Zealanders who advocate for pragmatic regulation and support stressed out farmers.
Rockit Global has appointed Ivan Angland as its new chief operating officer as it continues its growth strategy into 2025.
Nominations are now open for the Horticulture New Zealand (HortNZ) board.
A Mid-Canterbury dairy farmer is bringing a millennial mindset to his family farm and is reaping the rewards, with a 50% uplift in milksolids production since he took over.
OPINION: People have criticised Christopher Luxon for the time he’s taken to appoint a new chief science advisor.
A new Indonesian school milk programme is expected to significantly increase the country's total dairy consumption, creating opportunities for New Zealand and other global dairy players.
OPINION: Last week's announcement of Prime Minister’s new Science and Technology Advisory Council hasn’t gone down too well in the…
OPINION: At its recent annual general meeting, Federated Farmers’ Auckland province called for New Zealand to withdraw from the Paris…