Climate change ‘in the field’
While politicians assess climate change in terms of global statistics and carbon emissions, Queensland farmers Kerrie McMartin and her parents Graham and Lillian have a far more ‘hands-on’ appreciation of changing weather trends. John Power reports.
OPERATOR: McMartin’s Farm
REPRESENTATIVE: Kerrie McMartin
LOCATION: Bli Bli, Sunshine Coast, Qld
For two generations, the McMartin family, including parents Graham and Lillian and their daughter Kerrie, has farmed land at Bli Bli on the Sunshine Coast, Queensland.
Over the years the McMartins have developed an intricate knowledge of their local environment and its behaviour, and witnessed significant alterations in long-term climatic trends.
These climatic changes, Kerrie said, include more extreme and prolonged dry and wet spells, greater temperature fluctuations, stronger winds, rising water levels of the Maroochy River, and a disturbing unpredictability in day-to-day weather conditions (a new ‘weather disorder’ has displaced ‘weather patterns’ and shifted the boundaries of traditional seasonality).
Understandably, such intense volatility has affected every aspect of the farm and its operations, leading to more reactive and remedial responses to crop and water management, as well as revised attitudes toward equipment procurement and usage.
McMartin’s Farm consists of two adjacent holdings: the 65-acre Home Farm features 1,000 custard apple trees, a small lychee planting, as well as a ‘pick your own’ strawberry farm; and across the road is the 190-acre Cane Farm (expanded just a few years ago), which is planted primarily with sugar cane and more lychees. The family also grows a small number of fig trees.
Kerrie and her parents perform the lion’s share of work on their own, helped by one worker for part of the year and a small number of transient planters and pickers.
The nature of the work is reflected in the fleet of outdoor power equipment used on the two properties; and, as we will discuss later, recent changes to the composition of the fleet provide clear insights into the troubling effects of climate change.
NEW PROBLEMS, NEW EQUIPMENT
While McMartin’s Farm remains profitable – certainly, overall production has fallen in recent years – its viability is under constant threat, most obviously from rising river levels and associated salinity and drainage problems.
“The Home Farm backs on to the Maroochy River, which is saltwater, and sea levels are definitely rising – we’ve already lost one paddock to salt inundation,” Kerrie said. “And at Cane Farm, which is 80 per cent below the high tide level, we have a drainage system to make sure salt doesn’t come into the land.”
Inundation from heavy and erratic rainfall can be just as devastating as tidal flooding, Kerrie explained, as unexpected downpours at unusual times of the year can wreak havoc on new plantings.
“We might go through periods of six months of wet and six months of dry, or four months of wet and three months of dry, instead of having regular rainfall throughout the year,” she said.
“The land can’t handle it and it leaves crops, especially sugar cane that has just been planted, very vulnerable to damage because the sun heats the water and kind of ‘cooks’ the sets when they’re trying to grow.”
In response to rising river levels and erratic downpours, the farm has suddenly become reliant on water pump systems to remove excess water and stabilise soil moisture. Until recently, water pumps were never regarded as vital pieces of equipment on the farm.
Last year a 24” three-propeller water pump was in action for 300 hours to remove excess water from the property, “Which is ridiculous – we never pumped that amount in the past,” Kerrie noted. Next year, she added, the family will install a larger 30” pump.
Not only has the family had to embrace previously unneeded water pump technologies, but weather extremes have also caused elevated insect and weed infestations, requiring more spraying activity than ever before. This means that sprayers, like the farm’s water pumps, have unexpectedly gained prominence amongst the business’ core fleet of equipment. A Gator sprayer with a 200L tank and handheld wand is used to control weeds, while a John Deere 6410 is also equipped with a sprayer. In addition, an older John Deere 2130 with a 900L tank is crucial to safeguard crop health.
WHOLE FLEET AFFECTED
Even more ubiquitous items of farm equipment, including smaller handheld devices like chainsaws, are not immune from the effects of prevailing climatic conditions.
As Kerrie pointed out, all of the property’s equipment is ageing, but replacement and maintenance budgets have taken a hit following declines in crop production.
At present, apart from the abovementioned items, the property’s equipment inventory includes three STIHL chainsaws of different sizes, including a small lightweight pruning saw and boom saw; three STIHL whipper snippers; Infaco electric pruning shears; a John Deere 6810 tractor; a second John Deere 6410 tractor is used for mowing and mulching; as well as older 2030 and 3130 John Deere tractors used for general duties. Specialist equipment includes a Woodland Mills wood chipper, as well as an Agtrack cherry picker for picking lychees, plus plastic sheet laying and lifting apparatus from Glasshouse Design and Manufacturing for use on the strawberry fields.
Historically, Kerrie said, the farm used to enjoy frequent turnovers of machinery, particularly large tractors, in lease cycles of three years or so. Nowadays, all outdoor equipment from the humblest whipper snipper to the largest tractor is fully owned to squeeze out longer equipment lifespans.
“It comes down to what your highest priority is,” she said, “and generally that means ‘getting something done’. If an equipment failure means a task cannot be done, well then – and only then – will it be repaired or replaced.”
This frugal approach, Kerrie admited, can be frustrating, as it means new equipment is purchased only when older items have expired – some tractors on the property are approximately 40 years old, and will remain in operation for as long as practicable.
Another problem with a slow turnover of machinery, she said, relates to the delayed adoption of new, more efficient technologies such as battery-powered devices.
“Battery-powered chainsaws are amazing now, and I have arborist friends who use them all the time, but I would only get one when an older chainsaw dies.”
Electric devices, Kerrie said, are not only cheaper to run, but they could also be charged from the property’s own recently installed 35kW solar array. (NB. there are plans to fully electrify the irrigation system, which is served currently by both electric and diesel pumps.)
Needless to say, decisions to retain older equipment for longer periods have direct consequences on the businesses of local sales and service dealerships, as well as the immediate efficiency of farm operations.
FEELING THE HEAT
Of course, one of the most recognised effects of climate change is a gradual increase in average temperatures. Higher temperatures are extremely problematic for tropical orchards like custard apples if there is low rainfall, Kerrie explained, as the fruit needs high humidity levels in Oct-Dec to set properly. Alas, rainfall was low last year, which meant the heat dried out the landscape without the usual palliative humidity.
To make matters worse, low humidity levels were aggravated by unusually strong winds – another by-product of climate change – which served to dry out the topsoil even further. While irrigation alleviated the dryness, the strong winds created a secondary operational problem by limiting the effectiveness of spraying.
“The winds meant I could only spray between 5.30am-7am [the least windy time of the day], whereas sprays might normally be applied any time before midday under normal circumstances,” Kerrie said.
USE MORE MULCH
While mulching is an effective weapon against increasing temperatures and a useful tool for enhancing localised humidity, Kerrie advised it is not without its perils.
Last year Kerrie applied sugar cane mulch for the first time to the custard apple orchard, which, she believes, definitely improved moisture retention and improved the soil.
Nevertheless, mulching often calls for a sensitive understanding of the fine difference between a ‘protective covering’ and ‘harmful heat blanket’; for instance, when applied to sugar cane fields, layers of green waste – known locally as a ‘trash blanket’ – must be monitored closely to ensure the mulch does not become a heat sink on days when high temperatures combine with unanticipated heavy rainfall.
CLIMATE CHANGE, CHANGE JOBS?
In light of so many obstacles and uncertainties, does farming have a future on the Sunshine Coast?
“You kind of get to the point where you say, ‘Why would I want to work all these hours and not get financially compensated,’ and it’s horrible – that’s what farming’s like now,” Kerrie lamented, describing the Sunshine Coast as the “fastest declining agricultural area in the country”.
While Kerrie and her family are adamant that they will adapt to new conditions and persist with farming, there is no denying that the real victim of climate change on the Sunshine Coast is farming itself.