GrassCo

A look at an innovative agricultural business measuring pasture dry matter on both dairy and sheep and beef farms.

Measuring dry matter on NZ sheep farms is not done routinely or regularly. Sometimes measurements are done at critical times such as before winter or if information is required to make management decisions. In contrast dairy farmers place a high value on routine measurement and use that information to predict and enhance productivity.

Sheep farmers have to manage what is a relatively consistent feed demand in an environment where feed supply is relatively inconsistent.

GrassCo grew out of the demand dairy farmers have for regular pasture cover information and a breakdown of that data to help them make good management decisions.

Beef and Lamb funded a project to investigate the feasibility of intensive weekly whole farm pasture cover measures to assist with management decisions, in a farmer initiated technology transfer.

More recently Grassco has become involved in a Red Meat partnership project where a sheep farm is being measured every 14 days. 

Grassco owner Donald Martin believes you have to measure to manage. His company has developed a highly modified pasture monitoring sledge towed behind a quad bike.  With the sledge he can measure the whole of the farm using a pasture meter.

Consistent paddock tracks are taken, guided by GPS and information is immediately available with details summarized as a pasture wedge graph.

Donald says the machine can measure roughly 100ha in an hour. Collected data includes kg DM/ha, cover in a paddock, residual grass and available grass.

A lot of work has gone into the GrassCo sledge design. The monitoring equipment is calibrated by AgResearch.

Cost per whole farm measurement is roughly $6,000 per annum.

The most accurate measure of pasture cover is to cut, weigh and dry all the material present but that’s not practical on farms.

Traditionally farmers have visually assessed pasture or used a rising plate meter or handheld devices such as probes. Plate meters are reliable as an estimate of pasture when at least 50 readings per paddock are taken, but this again takes time and is monotonous for the farmer, especially since this needs to be done regularly.

Recent innovations in pasture measurement include C-DAX – a pasture meter that uses a laser to measure grass covers. The device can be towed behind an ATV or a car. Other technology uses sound technology, similar to fish finders to measure pasture height. There are also remote sensing devices using SAR – synthetic aperture radar and NIR (near infrared) which are being developed for pasture and already in use for crops. But so far there isn’t a reliable technology that would enable farmers to measure pasture quality.

The bulk of GrassCo’s clients are dairy farmers in Otago and Southland who get their pastures measured weekly. “It’s consistent reliable data, measuring a paddock with the same GOS track weekly at the same time.” Farmers who have pasture measured weekly are also able to assess average daily growth.

Donald is in his seventh season with the pasture measurement work. He’s covering between 1000 – 1400 ha a day.

Collected data can be used in management software and available soon after the paddock has been measured. Donald says he downloads the information to his laptop, sends it to the office where it is edited and put into a template and sent to the customer.

Donald Martin says key farm decisions can be made with the help of this regular pasture measurement. He says weekly measurement itself does not lift production, it is how that data is used that counts. He also says the more production data is collected on sheep performance, the more useful the weekly pasture cover data will become. Each year’s growth pattern is different and regular measurement provides an early warning of problems and opportunities.

Donald says sheep and beef farmers are slowly catching on to the benefits, using it monthly during spring, summer and autumn.

He says thousands of dollars goes into genetics and fertilizer but very little focus has been placed on the monitoring of grass. On one farm where trial work was conducted using Grassco, an additional benefit to the regular feed wedge information was the ability to rank paddocks for productivity. He says the power of the information gathered will increase as more years’ data is collected.

Neil Ross has recently returned to farming after a number of years running a jet boat tourism business in Queenstown.   He runs 208ha at Te Tipau south of Gore. The property has 800 ewes and 1400 hoggets. He says coming back to farming has encouraged him to look at farm management in a different light.

He started using GrassCo as he was preparing for winter and trying to estimate how much feed he had for the stock he was carrying.   He says knowing what his feed wedge looks like makes management much easier. He says he can travel away, leaving the farm in the hands of a manager, knowing that the food is there for his animals. Using Grassco has taken the guess work out of a basic but important part of farm management.

Grassco has five sites in Southland where soil temperatures are measured and a site where air temperature is monitored. With that added detail to the pasture monitoring, Donald believes he has a very accurate, regular snapshot of growth and quality.

Another innovation he is trying is the use of E temperature buttons. The buttons are roughly the size of a coin battery and were originally designed for use in cool chains and in the transport of perishable goods. They read and log temperature readings. That data can be transferred to a computer.

Donald buries them around the farm and uses that information to take the guesswork out of predicting when grass will begin growing. “Ryegrass doesn’t really kick in until the soil is above 6 degrees and clover above 14.”