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Californian Thistle.
Like a martial art, sustainable and smart pest and disease management relies on understanding opponents’ strengths and weaknesses and using these against them, says Charles Merfield of Lincoln University’s biological husbandry unit (BHU).
That means putting much more emphasis on biological and ecological control, and reducing reliance on physical and chemical attacks.
“You need to understand how these things are working and start developing the strategies,” he told one of a series of FAR workshops on sustainable agriculture and horticulture (see main story).
For every pest or disease, consider host range, dispersal method, conditions conducive to development and reproductive rate. A similar thought process can be applied to promoting “beneficial” bugs which predate on insect pests or weeds. “There’s a lot of free pest control going on out there. Let’s try to improve that.”
Similarly, with smart cultural techniques, near-complete weed control can be achieved without herbicides so even open canopy crops such as beet face little competition. “It’s very, very simple. Grow the weeds, then grow the crop.”
If herbicides are used to remove what does come through after sowing, there’s a reduced risk of selecting for resistance simply because there are fewer weeds.
Huge advances in hi-tech auto-guided mechanical weeding machines have been made but in some cases the combination of simple old-school techniques like inter-row hoeing with GPS guidance can allow faster and longer operation, achieving just as good results for relatively little cost. Soil flicked up by the hoes buries the most difficult weeds to reach – those by the crop plant stems – hopefully killing them, he explains.
Whether such a technique works, again comes back to knowing your enemy. “To kill a plant you’ve got to kill the meristem.”
Some weeds, such as dock, won’t regenerate from roots, only the crowns, so decapitating them is all that’s needed. Others, such as dandelion, will push up new crowns even if the root is severed well below ground, but an annual thistle take-off at the hypocotyl (where stem meets root) is “toast”, hence why a grubber works.
Another key point is that cultivation triggers weed germination, and most weed seeds won’t germinate from deeper than one inch so cultivation to remove already growing weeds shouldn’t go below that depth if triggering a fresh flush of weeds is to be avoided.
But for all the merits of false and stale seed-bed preparation – Merfield defines the latter as created post-sowing with chemical or thermal control rather than cultivation – at the top of his hierarchy of non-chemical weed controls is rotation, with a mix of autumn and spring sown crops and pasture phases included.
“Rotation, rotation, rotation,” he says, mimicking the real estate ‘location’ catch-cry.
To survive and thrive in this changing world, New Zealand farmers must take a new look at what resilience means to them and their farming operations, Foundation for Arable Research (FAR) chief executive Alison Stewart says.
Agronomic tools and practices are available for maize growers facing the headwinds of increasing costs of production, extreme weather events and environmental considerations, Foundation for Arable Research senior maize researcher David Densley says.
Arable farmers are being encouraged to vote before the August 23 deadline in a referendum, which will determine the future of the Foundation for Arable Research (FAR).
Planting green a developing trend here and overseas where growers plant directly into a green crop, will be demonstrated at the Foundation for Arable Research (FAR) premier maize field day near Hamilton this month.
Climate change could make maize silage a more realistic fodder proposition for South Island dairy farmers, according to researchers speaking at the recent Foundation for Arable Research (FAR) CROPS 2022 event.
Federated Farmers president Wayne Langford is claiming “some real success” on the 12 policy priorities it placed before the Coalition Government.
Federated Farmers is throwing its support behind the Fast-track Approvals Bill introduced by the Coalition Government to enable a fast-track decision-making process for infrastructure and development projects.
The latest report from ANZ isn’t good news for sheep farmers: lamb returns are forecast to remain low.
Divine table grapes that herald the start of a brand-new industry in Hawke’s Bay have been coming off vines in Maraekakaho.
In what appears to be a casualty of the downturn in the agricultural sector, a well-known machinery brand is now in the hands of liquidators and owing creditors $6.6 million.
One of New Zealand’s deepest breeder Jersey herds – known for its enduring connection through cattle with the UK’s longest reigning monarch, Queen Elizabeth II – will host its 75th anniversary celebration sale on-farm on April 22.
