Davis Vantage Pro2 Weather Station used at Arable Farm

Posted in Farming.

LeafWetnessSimon Collins is the Senior Partner at MJ & SC Collins, a family business started by his parents in 1961. The farm is spread over 5 sites covering just over 3000 acres on the Hertfordshire / Essex border. Crops include wheat, OSR and field beans. The locations are up to 12 miles apart, with a multi-site visit taking over an hour to visit Sawbridgeworth, Matching Green, and Harlow.

Although the sites are in relatively close distance, Simon advises that there are very localised weather conditions which affect operations. The team already know that it can be raining at one site, but not at others. Simon is conscious that their equipment could be better used at a site where it is not raining for spraying or harvesting, but to drive there to find out the weather conditions takes an hour of time, increasing diesel costs, and with farm equipment and staff standing waiting. Time is at a massive premium in summer, and there is pressure on the combine to get grain into stores whilst it is dry, before any onset of rain. With crop drying costs already high and still rising, John Haynes, the farm manager needs to know what is happening on different sites at any one moment. In addition, the farm has c.1150 photovoltaic panels at 2 sites. Simon wanted to ensure the weather stations were able to have a solar sensor to provide an independent check of the readings given directly from the photovoltaic installation.

It had been in the back of Simon’s mind to install automatic weather stations on at least two sites, whilst the farm manager’s residence already has one at a third site. Leading up to 2012, and with a change in farm manager who already owns a basic weather station, it was decided the time had come to research which stations would meet the farms requirements. Simon required a sophisticated system to provide accurate readings which would give great connectivity. Connectivity was key, as Simon wanted to provide real live weather conditions on smart phones for John the farm manager, Garry the spray operator, and Simon’s son Peter, who is often driving the combine. As they all have Blackberrys, they wanted to check weather conditions from the cabs of their machines.

Simon researched weather stations technical specifications and found that the Davis Instruments Vantage Pro2 was most likely the product he wanted. Because Davis have a long list of agricultural accessories which provide the ability to add remote soil and leaf wetness sensors, the system was attractive to future proof against any land and crop changes. After selecting the Davis Vantage Pro2, Simon looked at price and was deciding between two companies. There were some unanswered questions so picked up the phone to speak with both companies. Simon found EnviroMonitors “were knowledgeable, helpful and provided guidance for my decision making”.

In February 2012, Simon purchased from EnviroMonitors, two Davis Instruments Vantage Pro2 wireless weather stations with IP WeatherLink for the Matching Green and Harlow sites. In addition, each system has a separate transmitter to monitor leaf wetness to indicate rain, dew and speed of evapotranspiration. John the farm manager lives on the site at Sawbridgeworth with his basic weather station. The plan is to enhance monitoring at this site with the more advanced Davis system and specialist leaf wetness sensor.

The equipment arrived on time and the manual was found to be logical, written in good English (as opposed to translated English) so is easy to understand, and includes precise instructions. Simon confirms “if you read it once and don’t quite understand, then it read again, it does make sense, and it is factually & technically correct”. As advised by EnviroMonitors, Simon assembled the system on his office floor to check the set-up was correct and the console was receiving from all sensors before installing outside.

Kingston Farms

Alot of thought went into the most suitable locations for sensor placement as Simon adheres to the old analogy “Rubbish In, Rubbish Out”. The anemometer was located in a more ‘meteorological’ position (6 metres on a steel pole in clear airflow) instead of at crop height which would only provide indication of spray drift at the crop location. Wind direction is crucial as a management tool for John, so Simon chose to have accurate readings rather than getting inconsistent readings at crop height. To locate at crop height would have been too close to buildings resulting in wind direction readings being affected by eddying. The leaf wetness sensors also needed careful consideration. At one site the leaf wetness sensor is on a gate post at a lower level for the crop and at the other it is attached to the main pole. Simon believes the rain gauge is currently shadowing the leaf wetness sensor which is attached to the main pole therefore it is providing drier than actual results. A smaller stub pole is to be sited next to the main one to push the leaf wetness sensor away from the lee of the rain gauge.

John uses the weather stations everyday. At 6.30am he logs into weatherlink.com from his home PC to understand the current conditions. Then throughout the day he looks at his Blackberry for readings of temperature, wind direction and strength, when the last rain fell and the leaf wetness level. Simon says this is “great to have it real time and is especially useful when the weather is erratic”. Having 2 weather stations at sites where John does not live means he can “save an hour of time which is already short, and saves the cost and environmental impact of diesel driving across to the sites”. As the weather is usually different across the 3 sites, it helps him plan where to direct the machinery and timing of jobs, with “no end of information available such as high and lows and when events occurred” such as heavy rainfall. Instead of basing any decisions on the real time information only, John looks at trends to build up a picture of the conditions the crops have endured and how they are looking compared to previous conditions they have experienced.

Leaf wetness sensors have worked really well as an indicator for determining heavy dew and showers. Farm Manager John comments “the leaf wetness sensor in particular helps with crop spraying both with knowing when to deploy the sprayer and where the best place to go is……looking every 30 minutes, I can see the value lowering and can work out when it will be dry to deploy sprayers”. If the leaf wetness reading is coming down quickly John calculates when they shall be able to spray the crop in that location, if it is slower then he can prioritise another drier site. The sensor gives a value between 0-15 and Simon advises “it has been a learning curve of which reading is best for which crop”. As John advised, the speed the reading reduces affects his timings, and this speed varies according to the crop. OSR is dense and so takes longer to dry out, for example a 7 may mean a 10. Beans however is a thin crop, so at a reading of 5 you can probably spray. If John is not around, Garry the spray operator can see the weather at both sites on his Blackberry to make an informed decision on where to head for. Simon adds “when we are looking to put over £300K of chemicals through the crop sprayer, it’s a huge waste in wash off and for the environment if the conditions are not suitable”. The team are able to base spray decisions on the current conditions provided by the live weather station readings.

To conclude, John finds that “it is fantastic to automatically know what the conditions are, with current economic climate and constraints, it is best to have as much information as you can. I am now calibrating myself to the conditions using my growing knowledge of how the readings on the leaf wetness sensor correlate to conditions in the crop, so that I can be positive with decisions”. Simon feels “We have been fascinated how the weather station automatically records the periods of wet & dry to look back on, with the Davis software giving many varied display options for downloaded data. It has assisted my farm manager to make informed decisions which reduces costs and protects the environment; so it has proved its worth already. I am expecting it to be very helpful for the time critical harvesting and subsequent cultivation and seeding”.