written by Wayne Knight; HMI Executive Director, HMI Certified Educator, and Rancher
With the change of season approaching, it the time of the year to measure forage assessments for
the dormant season grazing plan in much of the northern hemisphere.
There are many ways to access how much forage you have been able to grow in the growing season.
(I recommend the STAC method which you can find free on our website at:
The volume of forage is only 1 data point. The other critical information point is the time over which
you need to allocate out the forage. With the increasing variability of onset on amount of rain, this
time span is a critically important consideration in the planning process. Allocate too little time in a
drought year and you will be out of forage if the rains arrive late. That translates to expensive
substitute feed costs, poor animal performance and probably deteriorating ecosystem function.
Conversely, by allocating too much time, you could land up with unused forage which translates to
forgone income and a poor mineral cycle when the rains arrive. Unused forage that spoils is a waste
of resource and lost opportunity to sell solar dollars in the form of livestock.
The time allocation will surely be influenced by many factors like the timing of you production cycle
relative to the start of the growing season, the brittleness of your environment, and how much risk
you can afford to expose your business to.
Analyzing rainfall and the likelihood of later than expected onset of the growing season is very
helpful for informing forage allocation and destocking decisions. I used 20 years of rainfall data to
determine the likelihood of onset of growth and the same data to view the latest onset of growth to
determine how much time should be allocated to get through to growth season in a drought event.
Bud Williams talked about the three inventories of risk in a ranching business: livestock, forage and
cashflow. His observation was that a rancher could run out of animals and cashflow and still survive,
but that a rancher could never afford to run out of grass. The cost and risk of being out of forage will
sink the business very fast – economically hay feeding is very bad for the economics and balance
sheet. Running out of forage is also bad for animal performance and for ecosystem function and the
time it will take to grow new forage when growing conditions return.
Spending appropriate time on considering what forage you have going into the dormant season to
get you soundly through to a potentially conservative estimate of the start of your next growing
season is one of the most important considerations for a grazing business. Learn the basics of how to
do this at one of HMI’s Training Programs.