What is the primary concern regarding overly lush, green pasture in the spring?

Answer

Grass sugar and starch levels (NSCs) are very high.

During the spring, lush grass contains very high levels of Non-Structural Carbohydrates (NSCs), which can cause metabolic upset in mules, unlike horses which may handle it better.

What is the primary concern regarding overly lush, green pasture in the spring?
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