Ben farms at Moree, New South Wales, and his interest in technology has taken him to the USA as a Nuffield Scholar (2014) and has now led him to create a business providing satellite mapping services to other growers and agronomists. Satamap presents satellite images in a way that enables users to compare images taken at different times and to analyse them for variations in vegetation, which has proven particularly useful in finding problem areas on farms, such as weeds.
Ben said that by using the satellite images, agronomists can look for anomalies in biomass production on their clients’ farms and can then go directly to the area on the farm to identify the problem
“In the case of weeds, it is easy to calculate the size of weedy patches and to monitor the impact of herbicide or cultural practices,” Ben said.
“An example on our own farm was to clearly see the impact when we sprayed a paddock where awnless barnyard grass was a problem and were not able to get back with the second knock due to rain. The recovery and spread of what we now know for sure was glyphosate resistant barnyard grass showed very clearly in the satellite images taken before and after the event.”
Agronomists use Satamap to observe trends across their district and to make their farm visits more time efficient. In fallow paddocks the satellite images show the extent of vegetation (weed) growth that can be hard to see in tall stubble. The images show an average reflectance over a 10m by 10m area, so a similar sized patch on the map may represent a number of large individual plants spread out across the area, or a carpet of grass.
“It’s important to ground truth what you see on the maps,” Ben said.
“And it’s also important to realise that if you don’t see anything, it doesn’t mean you don’t have weeds. It’s not going to find three plants in a paddock or very patchy distribution across a paddock, but areas of a few square metres or more you will most likely be able to see.
“Some agronomists are using imagery from the previous year to plan variable rate application of pre-emergent herbicide to treat areas where the weed seed bank could be expected to be high in paddocks with known problems.”
B&W Rural agronomist Brad Donald has been using Satamap for a few years now and describes it as a very useful tool.
“It enhances what we already do,” Brad said. “It gives us spatial data to base decisions on and enables us to be more proactive in managing problems.
“In one paddock I help manage, we had an issue when the operator ran out of chemical when they were spraying. Of course, he refilled and carried on, but on the images, we can clearly see a section where the boomspray missed – there’s a strip of black oats a boomspray wide and 100m long. We know there’s going to be a larger seedbank in that area so we can go back and do some extra mopping up. We can be proactive in monitoring and managing it, rather than waiting until it becomes a problem and being reactive.
“Satamap is also very useful in finding herbicide resistant weeds,” Brad said.
“If you check the images before and after a spray application, you can see where there are areas of weeds remaining. That gives you a clue that you may have a resistance problem developing, so you can go back and treat with a different herbicide group to get on top of it before it becomes a real problem.
“Being able to see things from a different perspective gives you more of an idea of what is going on in the paddock.”
Ben said the satellite images are not a diagnostic tool on their own, but should rather be used to provide additional information to the grower and their advisors.
“In our area, it’s really good for finding the summer grasses growing in fallows,” he said. “When we have big falls of summer rain followed by warm weather, we get widespread germination of crop weeds like barnyard grass and feathertop Rhodes grass. As it dries off and the grasses get stressed, they become very hard to kill, so being able to identify problem areas quickly is very useful. You can see them on the maps and then go out and see exactly what’s happening on the ground.”
For more information about managing herbicide resistance visit the WeedSmart website.
Contact:
Ben Boughton, Satamap
0428 548 688
Brad Donald, B&W Rural
0427 103 739
