Boost Soil Health with Broadleaf Crops

By Scout Nelson

In Western South Dakota, crop rotation decisions are critical due to limited rainfall and short growing seasons. No-till systems have improved water retention, allowing more cropping options, especially broadleaf crops.

Effective crop rotation depends on intensity, variety, and profitability. Intensity refers to efficient water use. Variety helps control weeds and pests. Profitability ensures economic success for current and future operations.

While wheat and corn provide residue that supports no-till practices, broadleaf crops are also important. Common choices include peas, soybeans, and sunflowers. These crops add variety but pose challenges.

Sunflowers have long been popular in South Dakota, but issues like pests and disease, including insecticide-resistant weevils and stem canker, have increased. Markets have also declined since 2022.

Sunflowers also consume high amounts of water and nitrogen and produce low residue, making it hard to protect soil after harvest. This can increase erosion risk and reduce soil health.

To reduce these issues, farmers are advised to rotate different broadleaf crops less frequently—every four to five years—and mix cool- and warm-season varieties.

Alternatives like canola offer strong markets and better environmental performance. In 2024, canola near Martin, South Dakota, yielded 1,500 pounds per acre and produced high dry residue, up to 3,500 pounds per acre. This residue helps retain snow and moisture.

Other promising crops include flax and camelina. These oilseeds have short growing seasons, tolerate drought, and resist pests and herbicides, making them suitable for South Dakota conditions.

However, risks like seed shattering in dry heat remain. Careful planning is needed when introducing new crops.

In summary, rotating broadleaf crops with grass supports soil health and long-term farm success. Canola, camelina, and flax are good options for improving sustainability in South Dakota cropping systems.

Photo Credits:gettyimages-sasiistock