Threats to crop production: a brief tour

When I started out at the citrus desk at a commodity ingredients firm in 2000, Florida produced 75 percent of the oranges in the United States, and represented 20 percent of the global orange supply. Today it's closer to 50 percent and five percent, respectively.

One of the main drivers of this is crop disease. By 2005, three citrus diseases had taken permanent hold in Florida: citrus canker, and two insect-vectored diseases, Citrus tristeza virus and citrus greening (AKA Huanglongbing, commonly referred to as HLB). The result: Florida has represented about 90 percent of the decline in U.S. orange acreage in the past decade:

Chart showing decrease in U.S. orange acreage from 2013-2023
Source: USDA

What had been a $9 billion-plus industry is a shell of its former self, and the trend is accelerating. In just the last five years, Florida orange juice production declined from three million tons to 638 thousand tons. And despite all efforts, HLB-infected trees have now been detected in California and Texas, which are responsible for most of the remaining U.S. citrus production.

Not to keep piling on, but there are many other disasters lurking around the corner. In the late 1990s, the arrival of the glassy-winged sharpshooter (GWSS) in California sparked an outbreak of Pierce's Disease in winegrapes. GWSS vectors the bacteria responsible for the disease. It has no treatments and no cure, other than ripping out entire vineyards. GWSS and their native Californian relatives, blue-green sharpshooters, have subsequently spread Pierce's Disease throughout the state. While the large wine-growing areas of Oregon and Washington have been unaffected, is it too much to fathom that these insect vectors might someday find their way farther north, or into other wine-producing regions?

Map of California counties reporting Pierce's Disease in winegrapes
Source: https://www.cdfa.ca.gov/pdcp/images/PDdistributionByCounty.jpg

Even if you don't drink wine, you still have plenty to worry about. Subspecies of the pathogen that causes Pierce's Disease, Xylella fastidiosa, also afflict tree nuts, citrus, coffee, and olives, among other woody plant species. Tomatoes and cherries have their own pests and insect-vectored diseases that pose existential threats to these crops. And flying insects like Japanese Beetle and Spotted Lanternfly eat pretty much anything in their path - fruits, vegetables, nursery crops, urban trees, even lawns - and are spreading into new regions. In the closing weeks of 2023, we've seen reports of a new pest of concern to tree nuts in California (an industry with $6 billion-to-$9 billion in annual farmgate sales), and the publication of a study that suggests we may see major fruit and nut pests appearing up to a month earlier due to climate change, meaning growers will need to adopt additional monitoring and spraying regimes to protect their crops each year. Just a ballpark guess, but if that increases growing costs by $250 per acre, that could approach $1 billion in additional pest management costs in the western U.S. alone.

Management options are becoming more constrained

Over the past twenty years, insecticide resistance has grown at a frightening rate. From November 2023:

Graph showing increase in insecticide resistance from 1914 to 2023
Source: David Mota-Sanchez, Michigan State University (via LinkedIn)

More than 60 percent of the pesticide resistance records in the Arthropod Pesticide Resistance Database have occurred since 2000. If growers continue to run out of crop protection tools, either because they're losing effectiveness or because they are withdrawn from the market for other reasons, we're going to be in a lot of trouble.

We also need tools to better understand the problems

On a global scale, there are increasingly alarming reports of declines in insect abundance. While we are all aware of beneficial services such as pollination, for example, insects also less visible but vital roles in ecosystems, such as soil production and biological control of pests. While this study is a bit dated, research suggests that just a subset of ecological services provided by insects totals about $57 billion per year in the U.S.

But the scary part is that even with these reports, we still don't really know the full extent and nature of the insect decline. We need new tools to get the data. To illustrate, the Global Biodiversity Information Facility reports hundreds of millions of species occurrence records. Of the 103 million occurrences of class Insecta entered in the GBIF since 2003, only 0.2% were machine observations. The rest were made the old-fashioned way: by people going out and checking traps, using sweep nets, or sometimes just standing out in a field and counting them by hand. What if we could deploy sensors capable of improving on human data collection by a factor of 100? 1,000? This could have enormous implications for our understanding of natural systems, agriculture, and human welfare. It also hints at the need for raw computing power and advancements in data science necessary to get the job done.

So are we headed toward cascading ecosystem collapse? Widespread invasions of species that devastate crops, forests, and urban habitats? Or not? The fact that we don't really know should be cause for alarm by itself.

At the heart of it, I founded Resight Laboratories to help answer these kinds of questions. We are working to enhance the effectiveness of all of the management tools available for crop production and basic research.

To learn more about what we're working on and how it might fit in with your IPM programs, on-farm research, and product trials, please get in touch. I will be writing more about our work in the days ahead, so subscribe to our free newsletter to stay up to date.

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