Eric and Maxine Watson

June 2007
Life blood is often used to describe the sometimes precarious need for water to feed the farming industries in Canterbury. From large corporate dairy producers to intensive cropping operations the common thread is the rich seams of water underneath once parched soils, which many have been jostling for in recent years.

With the jostling for water take and the value increase in properties with water rights came environmental jurisdiction in the form of Environment Canterbury (Ecan) - a regional council that is keen to take on the role of watch dog.

Following a decade of what some farmers have described as haphazard granting of water take and a lack of serious knowledge about just how plentiful the Canterbury Plain aquifers really are, Ecan have become alarmed at dropping well levels in some parts of Mid Canterbury.

Since then gaining the right to take water has been a difficult and cumbersome process for those looking to develop farms and farmers have taken a consistent beating from urban media and public alike.

Yet in the background many have been fine tuning their properties to conserve water. These have been the stories that have not been in the mainstream media - until that is, the Lincoln University Foundation Rabobank Farmer of the Year competition decided to judge its 2006 award on irrigation and the question of sustainability of water on farm as a resource.

Wakanui cropping farmers Eric and Maxine Watson, took home the $15000 cash prize but more importantly were able to highlight to those critical of the need for water that the resource can be managed extremely effectively and conserved on farm with monitoring of both soil moisture levels and nitrogen uptake in plants.

Eric and Maxine have farmed with some form of irrigation all their married lives. Eric grew up with irrigation, some of his earliest memories are of the irrigation developments of the 1950s. On his fathers farm at Ealing the couple grappled with border dyke irrigation, which is still in existence on many such properties in Mid Canterbury today.

While border dykes were energy efficient the couple found they were certainly not water efficient with either a feast or a famine in water.

So when the couple shifted to Wakanui in 1992 (the shift was mostly because of the inefficiency and uncertain supply of water) and to spray irrigation it was a large learning curve. However, the wastage of water the couple had come to know under dykes previously also served to make them appreciative of the efficient use of water in spray systems and may have had some role in their continuing excellent steps towards further efficiencies.

The 490 hectare farm that is just 11 kilometres from Ashburton was set up reasonably well with two 306 metre Bisley lateral irrigators that ran parallel to each other in two strips of the farm. Water was taken from two wells at depths of 80 litres.

The laterals were among the first in the country and as such were prototypes. Along with that tag came the difficulty of getting servicing or gaining appropriate knowledge about how best to use them.

However, due to ageing machinery becoming unreliable , in 2001 one of the laterals was replaced by two T/L laterals and a T/L towable pivot was installed on previously dryland riverbed block. After a fire in 2004, the second Bisley was replaced by 2 321m Valley laterals, which in itself led to greater water conservation due to the couple being able to apply 40 litres per second through two machines instead of 80 litres a second through one large machine. This effectively doubled the use of water and applied the water at close to its infiltration rate at around 25mm per hour per machine.

Currently the Watsons consented water take is 202 litres per second which equates to 3.7 mm per hectare per day for a 70 day period. This gives them a total annual allocation of 259mm per hectare.

The Watsons estimate the water is applied at a cost of $1.37 to $1.45 per mm which shows why any saving can positively reflect on the end bank balance.

The two new laterals also meant up to date technology with an underground guidance system slashing the labour time involved in shifting machines from one side of the laneway to another, and stopping the laterals from getting stuck overnight on sticky spots on runs where in the past pools of water could have been wasted.

The change also gave the couple another 2 productive hectares in laneways that were now unneeded.

Having efficient irrigators has become one of the parts of the process on the Watson farm to using water efficiently. However, two of the key management tools the couple have used to farm sustain ably had nothing to do with the equipment itself and all lay around comprehensive monitoring.

The Mid Canterbury cropping industry has had a face transplant in the past decade. Cereals were the backbone of the county and those travelling through the region were more familiar with the golden ears of wheat and barley during the summer harvest months than they were of the rich and often vibrant colours of many of the specialist vegetable and pasture seed crops that are grown now.

Like most arable families the Watsons have been no different in decreasing their overall cereal tonnages in favour of a wide variety of specialist seed crops.

Take this year for example - in the 2006/07 season the couple will harvest 74 ha of wheat, 60 ha of fescue and 36 ha of ryegrass. On top of that they will also harvest 40 ha of marrowfat peas, 28 ha linseed, 24 ha plantain, 11 ha borage, 3 ha edible chrysanthemums, 10 ha radish, 20.5 ha bok choy, 20.5 ha spinach, 20 ha dogstail, 25 ha tritikale, 12 ha wild rocket, 9 ha maize for grain, 3 ha mustard, 9 ha Chinese kale for seed, 22 ha fodder kale, 22 ha red clover, 8 ha Caucasian clover, 14 ha silage oats and 1 hectare of chicory.

With each and every one of these newer specialist crop options comes advancing knowledge of what each crop needs in water and in nitrogen. As the farming industry sponges up the technology age the repercussions in an increasingly idealistic green world are great.

Eric and Maxine have been deep soil testing for residual nitrogen since 2000 - a wise move considering the other implication of nitrogen and sustainable water use, namely nitrogen leaching into waterways and soils.

Depending on results of those tests for each cereal the couple will match the residual level of nitrogen in the soil with the expected crop yield to come up with a more accurate figure of how much nitrogen to put on.

In laymans terms it simply means the couple are not wasting nitrogen, money, labour or providing an environmental leaching nuisance.

As science catches up the couple have applied their thinking to ryegrass and fescue and are looking to extend their application to all specialist crops as well.

In Erics mind this is one of the key points of their operation and adds to their general philosophy on monitoring as a management tool just as monitoring soil moisture levels is perhaps the key to their entire watering operation on farm.

It was also what former CEO of Meat New Zealand and now Lincoln University Foundation chairman Neil Taylor emphasized when choosing the couple as Foundation Farmers of the Year last December.

Mr Taylor said the Watsons and all the other finalists had demonstrated they were using water carefully and finely monitoring its usage. He believed the degree of sophistication shown by them on farm was outstanding.

Back on the farm the Watsons get on with life as usual. Every Friday Carol McGuinness from Hydro Services comes in to monitor 21 sites over the entire farm for soil moisture throughout the growing season. Carol does this by using neutron probes which monitor soil moisture depths at 0-300mm, 300-400mm and 400-600 - depending on the depth required by each crop.

She then gives an accurate reading of soil moisture available and the amount of water the plant is using. By that summary Carol is able to tell when the plant is going to come under stress and is able to advise when the Watsons should water their crop.

Eric has found the monitoring interesting as sometimes the soil moisture present in a crop is different to what he thought would have been there.

The couple spend $7000 a year on the monitoring service but it looks to be one of the most vital input expenses on farm.

The Watsons spend less than $20 per ha on monitoring soil moisture but that is more than paid for if they save just 15 mm per hectare on irrigating during the season, a figure they believe they probably do easily.

The third key area to sustainable water usage is minimum tillage, a practice where the less cultivation carried out on each crop each year equates to higher organic matter in the soil and therefore better soil moisture retention.

It also helps when farmers such as the Watsons are using long term crops such as fescue and Caucasian clover which may be in the ground for 5 to 6 harvests, leaving excellent organic matter and soil structure.

Some crops are also finished off by being baled for stock feed for winter cull cows or are shredded rather than burnt. This again returns organic matter to the soil rather than wasting it as a precious resource.Arable farmers have been moving steadily towards all these management practices.

As the climate becomes less and less predictable farmers such as Watsons are having to become better agronomists and forecasters in order to meet their targets.

The 2006-07 harvest season has shown how fickle the climate can be.

At the Watson farm 177.5mm of rain fell during December when normally very little rain would fall.

January turned in weeks of drizzly, overcast, great fungal disease manufacturing days, but recorded just 33 mm in comparison. In total the Watson farm recorded 890mm of rain for 2006 compared to 490mm in 2005.

Soil moisture monitoring has been more important than ever this year especially in January where the dewy January overcast days led many farmers to think their crops were getting enough water. However the drizzle did not equate to much in rain terms and it has been a tricky season in terms of when to water crops.

As global warming is projected to become a reality that we all must live with, so soil moisture monitoring and nitrogen testing must be the same.