Using a Rising Plate Meter as a Tool to Improve Pasture Management: Summer Project 2021

In Canada, grazing land, consisting of natural and planted pastures, accounts for approximately 50 million acres (Statistics Canada, 2011). Pastures provide numerous benefits to the producer, animals, and the surrounding environment. Grazing livestock on pasture provides economic benefits to the producer by supplying nutritious low-cost feed for livestock and utilizing marginal land not suitable for crop production (OMAFRA, 2015). Measuring and monitoring pasture growth on a regular basis can improve pasture performance, pasture productivity and livestock performance.

A rising plate meter is a tool that can assist producers in assessing the current state of their pastures, allowing them to make informed management decisions leading to better pasture and animal performance. The goal of this project was to demonstrate the effectiveness of measuring pasture using a rising plate meter at improving pasture management.

Materials and Methods

The primary site selected for this project was the Northwest Ranch at Victoria Community Pasture located in Hartley, ON. A secondary site, located in Nestleton ON, will be reported on later. The Northwest Ranch is 215 acres in size and is divided into eleven paddocks. The pasture was grazed by 110 heifers at a stocking rate of 0.51 animals per acre. Heifers consist of Angus, Simmental, Limousin, Charolais, and various crosses with an average weight of 625 lbs (284 kg). Heifers were turned out onto the Northwest Ranch for the 2021 grazing season in May and are still grazing this area. A rotational grazing system is implemented, with a rotation length of 32 days. The heifers have continuous access to an area know as the “swale” a low-lying area containing a water supply and access to minerals.

MEASURING PASTURE USING A RISING PLATE METER

On a weekly basis, compressed sward heights were taken from each grazable area (P1, P2, P3, P4, P5, P6, P7, P8, P9, and P11) using a rising plate meter. A rising plate meter has a round plate that rises to a height based on the amount of forage beneath it and this height is used to estimate pasture quantity. As the rising plate meter is pressed down into the forage, it counts the number of notches the plate rises (each notch represents half a cm). The first step in sampling with the rising plate meter was recording the initial counter reading. Next, a zig-zag path was taken across each field, and samples were taken at each stride to provide an accurate representation of field conditions. After, the end counter reading and the number of samples were recorded. On average, 200 plate samples were taken per pasture. It’s important to take as many plate samples as practically possible to achieve best representation of the state of the, i.e., areas with long and short grasses must be proportionally represented. Taking a high number of plate meter samples per pasture helps reduce the impact of operator error. In addition, it’s important to follow the same rough track in each field each week where possible.