7 June 2002

Spy-in-the-sky agronomy service set for take off

By Charles Abel

AERIAL imaging of crops to aid husbandry decisions is far from being pie in the sky. It is already bringing real benefits for one Cambs farm manager.

But this years validation work has highlighted a range of issues that will need resolving ahead of a possible commercial launch next spring.

"As it stands at the moment it is a useful management tool, but certainly not worth the £5 or £6/ha French farmers are paying," says Tim Whitehead, farm manager for Velcourts Vine Farm near Royston and a consultant for a French farmer group near Calais.

He is using the system to help plan crop inputs across 300ha of first wheat this season. So far it has helped fine tune nitrogen and pgr applications. But maps need to be available sooner and the advice the service offers needs recalibrating to UK farming practices, he suggests.

"There is no doubt that it highlights differences in the crop. In one field we drilled a strip of wheat after set-aside without Latitude take-all treatment. It stands out like a sore thumb in the images."

Indeed, the imaging itself is a big help when planning inputs, identifying areas needing in-field checks or rate adjustments. This years first images of post-winter crop growth were used to create simple operator maps so liquid nitrogen rate could be boosted 15% on thin areas and cut 15% on thicker areas, using an in-cab push-button control.

"Some of the areas we knew about already, but there were other areas that were new to us," admits Mr Whitehead. The aim was to boost all crop growth to the optimum for the time of year, so reducing lodging risk and boosting yield potential.

The second set of images showed that had largely been achieved, but suggested a few areas required extra attention to lodging risk.

"As a manager I was a bit sceptical, because I thought the first split-dose chlormequat had worked quite well."

Rates of Terpal (2-chloroethylphosphonic acid + mepiquat chloride) were varied from 0.5 to 1.5 litres/ha accordingly, but advice to delay the final 60-70kg/ha of the main nitrogen dressing until GS37/39 was less easily accepted.

With the crop looking hungry and commercial pressures to consider Mr Whitehead restricted the imaging advice to one split field. "Well see how that does, but I cant help thinking this part of the model needs fine-tuning to the UK farming situation. It looked like it was going to lose yield."

One possibility is that the way the model converts imaging data into advice could be geared too strongly to French crops, which require a different input regime.

The project partners are aware of the need to Anglicise the Cropstar service. "We knew we needed to validate the system, which is why we are testing it this year," says Syngentas Tom Robinson.

"We also need to see images two to three weeks earlier in the season," says Mr Whitehead.

That will not be a problem once imaging is done from satellite, rather than individual aircraft, notes Gary Holmes of imaging company Infoterra. &#42

Putting aerial imaging, already used in France, to the test in the UK are (from left) Rosie Bryson (Velcourt), Chris Rowsell (Syngenta), Tim Whitehead (Velcourt), Gary Holmes (Infoterra) and Tom Robinson (Syngenta).

achieved, but suggested a few areas required extra attention to lodging risk.

"As a manager I was a bit sceptical, because I thought the first split-dose chlormequat had worked quite well."

Rates of Terpal (2-chloroethylphosphonic acid + mepiquat chloride) were varied from 0.5 to 1.5 litres/ha accordingly, but advice to delay the final 60-70kg/ha of the main nitrogen dressing until GS37/39 was less easily accepted.

With the crop looking hungry and commercial pressures to consider Mr Whitehead restricted the imaging advice to one split field. "Well see how that does, but I cant help thinking this part of the model needs fine-tuning to the UK farming situation. It looked like it was going to lose yield."

One possibility is that the way the model converts imaging data into advice could be geared too strongly to French crops, which require a different input regime.

The project partners are aware of the need to Anglicise the Cropstar service. "We knew we needed to validate the system, which is why we are testing it this year," says Syngentas Tom Robinson.

"We also need to see images two to three weeks earlier in the season," says Mr Whitehead.

That will not be a problem once imaging is done from satellite, rather than individual aircraft, notes Gary Holmes of imaging company Infoterra. &#42

&#8226 Detailed aerial crop imaging.

&#8226 Interpreted maps aid agronomy.

&#8226 Needs adapting to UK farming.

&#8226 £5-6/ha cost to French farmers.

&#8226 Commercial in UK in 2003?

French farmers are already using a Cropstar-wheat service, paying k8-9/ha (£5.60-6.30/ha) for information showing how lodging risk, N status and post-winter crop growth varies across fields. In the UK, Syngenta has invested £200,000 in on-farm evaluation of the system, working with Infoterra, formerly the National Remote Sensing Centre, and management company Velcourt. A total of 51 fields will be monitored, representing 800ha (2000 acres) of winter wheat.