BROOKINGS, S.D. (AP) — A crop expert says the cold overnight lows in the forecast this week could hurt some of South Dakota's soybean harvest.

Agronomy field specialist David Karki with South Dakota Extension says freezing temperatures can cause up to a 5 to 15 percent yield loss if the plant hasn't reached maturity.

He says the maturity of this year's crop varies because rain in June delayed planting in much of the state, and it's been a cool growing season.

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