probablyasocialecologist:

Politicians on both sides of the aisle and the Biden administration have fallen for carbon offsetting’s simplistic appeal to fund carbon-smart farming practices without new regulations or government programs. But without a mandate to cut climate-warming pollution, buying unregulated carbon credits amounts to little more than misleading green marketing as companies maintain the status quo.

Soil carbon is hard to commodify, and offset sales lack basic market mechanisms. For one, naturally high variations in soil carbon concentration make it hard to generalize how certain practices, like no-till or planting cover crops, increase soil carbon sequestration. Soil carbon offsets also sell a claim to something that’s naturally impermanent – just one major disturbance or change in management practices can quickly release years of accumulated soil carbon.

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Major agribusiness companies like Cargill, Bayer, Corteva, and Nutrien have all launched private programs that purport to pay farmers for sequestering carbon. These projects let agrichemical companies define “climate-smart” agriculture in their image.  

Biodiverse, agroecological, and perennial farming methods have far greater climate and environmental benefits than implementing isolated practices like cover-cropping or no-till agriculture on conventional, monocrop farms. For instance, even by conservative estimates, agroforestry can sequester 10 to 20 times more carbon per acre than no-till or cover-cropping.

Yet virtually all agribusiness-led carbon payment programs only reward farmers for a limited set of practices that can be integrated into the conventional industrial approach to farming: reducing fertilizer use, reducing tillage, or planting cover crops. Bayer has a particular incentive to reward no-till and cover crop practices because most large-scale farms rely on glyphosate, the main ingredient in Bayer’s Roundup, to “knock down” cover crops and control weeds in lieu of tillage. We found that Bayer promotes using glyphosate to support no-till and cover crops.

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Corporate-run carbon contracts also aren’t a fair deal for farmers. While some programs tie payments to carbon-credit sales value, Bayer and Cargill unilaterally set the prices they pay per practice per acre or per ton of carbon sequestered. Carbon contracts are also long-term commitments. Farmers in Bayer’s Carbon Program must sign 10-year contracts with an additional 10-year “retention period,” during which farmers must maintain their new practices to ensure long-term carbon sequestration. This effectively commits farmers to 20 years of new fixed costs with only 10 years of guaranteed pay, at a price set by Bayer.