Despite long term and reliable studies indicating otherwise, some still question the validity of pasture Brix as a measurement of plant health and quality, stating that it is an irrelevant and flawed method of testing. However the reality is quite different!

Firstly, what is pasture Brix?

Pasture Brix is a measure of the amount of dissolved solids in plant sap solution. Put simply, it measures the amount of minerals and sugars dissolved in the plant tissue. Some say that because it doesn’t exclusively measure sugar levels, it isn’t relevant. But aren’t high sugar and mineral levels vital for animal performance?

Is pasture Brix really irrelevant?

Pasture Brix is a measure of the sugar and mineral content in the plant sap solution and to put it bluntly, the claim that Brix isn’t linked to pasture quality, production, animal nutrition, and health is wrong. Some argue that high sugar levels don’t result in higher production. In the cows themselves, rumen microbes use plant sugars to produce protein which is digested in the small intestine and used by the cow to produce milk. The higher the sugar levels, the greater the production. Studies have repeatedly shown that higher sugar content in pasture means better digestibility, animal growth, milk production and animal health, while grasses with higher mineral levels are better for animals and result in less need for expensive supplements.*

Plant roots use sugar for the energy they need to grow. Roots also leak a significant amount of sugar into the soil to nourish soil microbes, which through their digestive processes provide minerals and nutrients back to the roots, which the roots then use to grow a larger plant.

Now with all this explained, if Brix is a measure of sugar and mineral content of the grass, why would we not want higher Brix levels?

Brix gives farmers a simple, handheld tool to indirectly measure whether the plant is properly nourished. While it is sometimes not as robust as ME due to the effect the time of day, plant moisture, and frosts can have on results, Brix is a great measurement of pasture quality and has a strong correlation with ME tests, at a fraction of the cost and with no delay.

*Moorby, Jon, “Grass sugars make milk production sweeter” IGER Innovations, 2001, retrieved 6/11/08 from http://www.iger.bbsrc.ac.uk/Publications/Innovations/incon01.htm.  Abberton, Michael RASE Seminar 2009   “Plant breeding approaches to climate change mitigation in livestock agriculture”