A=RKLSCP and Other Farm Products

In the coming weeks the rhythm on the farm will change as kidding and planting ramp up. We are looking forward to the joys that the growing season brings but are also feeling the pinch of its oncoming tide; soon our days will be full of “farm work” and the time for planning and analysis will become vanishingly small. It will be get up and go time and we had better be ready.

One of the biggest things about farming that most people don’t see is how much careful planning and calculation goes into a season. People see weeding and harvesting and processing but they don’t see our crop plan excel sheet with its 65 columns per planting and its small army of pivot tables. Farming is a game of inches and that means there isn’t much room for error. The difference between success and failure, profit and burnout, can lay in the ability to make good decisions quickly amidst all the moving parts of the growing season. Some of this is on-the-fly decision making based on experience and knowledge of the systems involved (soil chemistry, physics, plant physiology…) but the base we work off of it has its roots in the work of winter and that work is mostly math.

A graph of egg production (showing atypically abysmal fall numbers)

It starts with record-keeping during the growing season: labor and inputs, growth rates, yields, processing volumes, soil tests, samples, sales. At intervals along the way, short spurts of analysis allow us to see how far off track we are and change our plans accordingly. At the end of the season all the data from the year, along with analysis done along the way, gets compiled and analyzed. The usual financial values sit alongside calculations for yield per row foot and per bed, by quarter, by month, by crop, by variety, even by location. We see what worked and what didn’t, how well our response to the unexpected performed, how the shopping patterns of our members matched up with our predictions. Then we make decisions for the next year and get the ball rolling.

A page from Andrew's notebook showing row spacing calculations

From soil tests and the individual requirements of our crops, we calculate the amendments our soils will need. (The equation in the title is for calculating annual soil loss due to erosion.) We calculate what we can grow where and when, including calculating our plant spacing, often unorthodox in our diverse system (in row, across row, diagonals, it’s a2+ b2 = cand then some). Then calculate on what day each plant will need to go into the ground, all the way until the end of the season. From there we put together a schedule of seeding, hardening off, and transplanting based on the needs of each crop. We calculate how many seeds to order based on our desired yield, spacing, germination rates, and anticipated loss. We calculate how much potting mix our seedlings will need. Then there are pests to worry about. The root maggots hatch when there have been 43 growing degree days: we calculate and track the growing degree days here on our hillside so we will be able to thwart them. On the animal front, we track the gilts’ temperatures to predict their ovulation times (2% drop 24 hours before, 4% drop 12 before). We can look at our grazing records from the previous year and calculate how much forage is growing in different parts of our pasture, how much our animals need (different for young, old, growing, pregnant…) and how we can fit all the pieces together to maximize the efficiency of and positive impact on our system.

An excerpt from the crop plan

I could go on and on (and on and on) but hopefully this little excerpt gives an idea of how much math and science we use on the farm each day. There’s more to it than meets the eye and it requires a lot of specialized knowledge. It’s certainly something anyone can learn but go in eyes open; you’ll spend as much time playing with numbers as you will playing in the dirt.

— Penelope