You might be familiar with the fact that in the U.S., an estimated 40% of food goes uneaten. That’s an alarming statistic on its own. This amount of wasted food correlates with waste in other areas: Around 21% of all water used in the U.S. and 18% of cropland is dedicated to food that will never get eaten, exercising a significant strain on already stressed resources.

But most of the traditional research into food waste looks only at what goes uneaten at the distribution, retail, and consumer levels. These measurements capture how much inventory grocery stores toss, for instance, or how much consumers let go rotten in their fridge without eating. When a team of researchers at the University of Santa Clara set out to figure out how much produce is wasted before it even leaves the fields, they found a much more dire picture.

According to the research team, around 33% of food that’s grown is either unharvested or left behind in the fields because the growers suspect it might not meet the specifications of their buyers. Growers often estimate the amount of produce they leave in the fields, but the Santa Clara team found, after conducting thorough analyses of 123 farms in northern and central California, that in-field food waste exceeds growers’ estimates of losses by around 157%. Some produce categories are more prone to waste than others: The Santa Clara team found that around 55.6% of cabbage was left behind, compared to just 4.7% of perennial artichokes. These variations are often due to how uniformly a crop grows (generally, growers are looking for a consistent product to offer buyers) and how frequently they’re harvested, on top of factors like crops’ resistance to variable weather.

But the findings from the study, while limited to a specific region in California, should wake growers up to the magnitude of loss likely happening in their fields. “The first step in addressing this problem is measuring it,” says Gregory Baker, executive director of the Center for Food Innovation and Entrepreneurship at Santa Clara University.

This developing understanding of in-field food loss could also, Baker adds, give rise to solutions to address it. One might involve partnering with food banks to ensure unsold produce makes it to people in need. Santa Clara undertook the study, Baker says, in part after conversations with the Second Harvest Food Bank of Santa Clara and San Mateo Counties, in which executives expressed concern that people living in poverty in the area were not able to access the vast amount of produce that’s grown locally.

Another solution might be creating a business market for this unsold produce. One of the problems, Baker says, is that there’s insufficient market demand for imperfect produce, the kind that’s most likely to be left in the fields. So there’s little incentive for growers to pay for the labor to harvest it if they’re just going to lose money and there’s no guaranteed market.

But some new companies are trying to correct that. Imperfect Produce packages and sells “wonky” produce at a discount directly to consumers, and so far has rescued over 40 million pounds of food. The startup Full Harvest works with farmers to source imperfect produce and help them sell it to food and beverage companies that can incorporate it into products. Full Harvest‘s CEO Christine Moseley founded the company after spending 15 years in supply-chain management and witnessing tons of food go to waste. The fact that over 30% of produce grown doesn’t even enter into the supply chain, she says, “is the next biggest stat to come out about food waste, because the 40% we always talk about for food waste doesn’t even include the food wasted on the farm.”