Heading into winter it is critical we have lots of high quality pasture on hand, pasture growth rates decline as the days shorten and our soils cool down.
To manage our pastures we monitor the pasture cover in each paddock every 10 to 14 days at this time of the year. Pastures are measured using an electronic meter to determine the kg of dry matter (kg DM) per hectare. The sensor is trailed behind our quad bike taking 200 measurements per second and matching the location of the measurements via GPS with the paddocks name.
The data collected from these measurements provides us with an understanding of how much feed we have available for our cows. A feed wedge graph is created to identifying potential feed surpluses or shortages.
Paddock Name
The sloping line represents our desired pasture cover. The cows are due to eat paddock 18 next and they have just come out off paddock 11, where they did a great job of eating what was offered to them. Today’s measurements show a slight pasture surplus, the average pasture cover for the farm today was 2413kg DM/ha, right where we want going into winter.
Pasture growth rate and leaf appearance interval is monitored to ensure our pastures are getting an appropriate rest interval between grazings. For the last 12 days our growth rate has averaged 27kg DM/day and our ryegrass pastures are producing a new leaf approximately every 14 days. We aim to graze pastures when each tiller has 3 leaves, giving us a desired grazing interval of 42 days.
This may sound like a complex approach to some thing seemingly simple like growing grass. Our pastures are integral to our business, with out grass we have lots of hungry cows, it is a case of look after the simple things and many other parts of the operation fall into place.
Montrose Dairy 
Interesting post, Graeme. What advantages does this offer over the Feeding Pastures for Profit approach?
The approach I take to pasture management is much the same as the Pastures for Profit method. Leaf appearance rate sets grazing interval and pasture cover available sets allocation and supplement level. The method used to measure these key factors isn’t critical. What is important I believe it is there is some form of measuring done. Using the electronic meter has confirmed to me my visual estimates were pretty close.
Thanks for that, Graeme. Do you find the metering method allows you to monitor not just the last ungrazed paddocks but also the more recent regrowth, giving you a more accurate picture of changing growth rates? Also, do you use the software to set the supplement levels or is that done “manually” by you? Sorry for the inquisition but it’s a very interesting post, especially given the story in the Aust Dairyfarmer not long ago.
It’s not feeling like an inquisition at all Marion,this is a subject which is core to our businesses and it gets paid very little attention. Thanks for the questions.
What ever method of measuring (rising plate meter, electronic meter and visual estimates), when doing a pasture walk I have always measured the entire milking platform. Understanding post grazing residuals (how well the cows have eaten out a paddock) is just as important to me as knowing how much the cows are going to be offered tomorrow.
All methods of monitoring require some form of calibration as the pasture changes through the season and they all have their limitations. I have chosen the electronic meter because when we need to keep up with our pasture recording most is during calving and I was finding I just wasn’t walking the farm enough. I can ride the farm, have a good look around/check things out and simply download when I get home.
I don’t generally use a software package to calculate the supplement levels, this is why I find the post grazing measurements so important. If the cows are leaving too much I remove some supplements from their diet. I do it this way because I never place too much faith in the calibration of any pasture DM measurement method and it must be remembered quantity is only one part, there is also a quality factor. In doing my pasture metering I’m looking for trends as much as definitive numbers. The focus changes with the season also, now my focus is getting the average farm cover up, in spring the key focus becomes post grazing residuals.
I do use a spreadsheet which is based on simple Target 10 type data to check the herd diet from time to time.
This response is full of contradictions I know, guess that is the nature of farming and as much as we try to monitor and measure there is still a significant intuition factor.
Thanks Graeme. Sounds like a really good routine you’ve set up. I do a “farm tour” once a week too but I suspect my pasture monitoring results carry a lot less precision!