Friendly Flock

When looking at pasture production we usually think in quantity of grass. So how many kg/ha of grass did I grow? Or how many bales of hay did I harvest. Also when measuring a pasture with, for example a plate meter, we look at the biomass production.

These are of course important measurements, we can then use to make decisions on our grazing.

So for example: We measured a field with a total biomass of 2000kg/ha of dry matter. We have 50cows which consume 15kg of dry matter / day.

When we take of , a percentage of grass non consumed, usually 30-50%, depending on the density we graze our livestock, we get lets say 1000kg/ha of dry matter. Ou field is 10ha big so we have a total forage availability of 20t.

With our 50 cows we consume 750kg/day. Which then gives us a total of 26.6 or 26 and a half day of grazing in the field.
In other words, we harvested 1300 animal days or 130 animal days / ha.

So where is the time management in all of this?

To limit overgrazing we have to manage essentially two things: the time, the animals stay on, and the time the animals stay off the pasture.

So the recovery period and the grazing period. Let’s focus on the recovery period.

When we are only locking at the quantity produced and not at time we will forget one of the most important things in grazing management: The recovery period of the pasture.

The recovery period is the time a pasture needs to completely recover. It can be quick or slow, depending on: grazing pressure, soil quality, weather, season, plant species community and personal objectives . How to determine the length of the recovery period is a subject for another article.

What’s important to keep in mind is , if we don’t respect the recovery period of the plants, we will overgraze and slowly diminish diversity and productivity.

So how do we manage for the recovery period we want?

First we need to know the time we want the pasture to recover, for example in spring we could say we need 30days of recovery.

Then we need the number of paddock, lets say we have 15.

Last we need to know the number of herds present on those paddocks. To make it simple we only have 1 herd.

This means: 30/(15-1) = 2.1 days in each paddock on average. Of course, to be exact we need to take into account the paddock quality and size. How exactly to do that I might explain in a later post.

So to resume: to limit overgrazing, it is crucial to manage for the right recovery period, so the time spent on and off a pasture. If you only look at quantity, you might get in trouble.