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For years, managers used the carbohydrate reserve theory to decide when to graze plants on rangelands to maintain healthy and desirable plants. The carbohydrate reserve theory states that the soluble carbohydrates stored in the roots and crowns of plants indicate plant health and ability to regrow after grazing. During the early vegetative stage of plant growth, carbohydrate “reserves” are low, so plants should not be grazed. During late vegetative and early reproductive stages of growth, carbohydrate “reserves” are higher, and plants can better tolerate grazing (see figure below). Over the years, researchers produced carbohydrate concentration curves for different grasses, forbs, and shrubs, like the one illustrated below. Unfortunately, carbohydrate reserves in plants are not good indicators of its ability to regrow after grazing for several reasons.