A recent Global Harvest Initiative study suggests that one-fifth of livestock are lost to diseases each year across the globe calling this the “perhaps greatest untold story of food waste today.” (See coverage at feedstuffs.com.) On the crop side, losses are also important. Joe Janzen’s story from two weeks ago, discussing reasons why organic land is expanding less rapidly than one might assume touches on the issue of disease risk—organic farmers have fewer tools to address pest and disease issues than conventional farmers do.
Whether or not we invest in research or use policy to address these diseases is dependent on how much harm we think they are doing—but this can often be a challenge to measure. Do we examine the cost of materials—such as pesticides and herbicides to control or prevent a pest infestation? What about labor hours spent, for example, monitoring or spraying? Or do we consider foregone revenue, compared to a situation where the diseases or pests were not present? Economists consider all of these things, but obtaining precise measures can be tricky. If the disease has always been around, it’s hard to compare current profits with those without disease.
Case in point: seed potatoes. I have a project with Nina Zidack, the director of the Montana Seed Potato Certification Lab looking at the costs of potato virus, and the benefits of the certification program. The Montana seed certification program is known for its low tolerance for virus. But those strict standards come with a cost—if seed does not meet the standards for recertification, growers face a large price discount to sell on another market, or potentially a cost of disposal.
We estimate the current costs from PVY losses in Montana range from roughly $3 to $10 per acre (using a rather limited definition) and estimates in other states are higher. Calculating the benefit from certification is more difficult. Without some sort of certification program, the seed potato industry would collapse, according to many growers. So is the benefit of the program the entire size of the industry? What about the commercial potato industry that grows the seed from the Montana seed program? These benefits get rather large, rather quickly.
Using data collected by the Montana Seed Potato Certification Lab, we can reasonably predict disease spread over the course of a season. If we do that for all the seed potatoes that come into the lab for testing, we can get an idea of what disease losses would be if the certification program disappeared for a year. Using this metric, we find benefits from the program of approximately $140,000 to $470,000 for Montana or an average of $14 to $46 per acre. However, these values provide a lower bound on the benefits from the program. The vast majority will be attributed to the commercial industry, which depends on clean seed for production.