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Jerusalem artichoke (Helianthus tuberosusL.) can be a weed in pastures and crops or used as silage, but little is known about its N and mineral content and their contribution to forage quality. This study evaluated 19 wild and cultivated genotypes of perennial Jerusalem artichoke for protein and mineral concentrations at various stages of maturity, and compared these to an annual cultivated sunflower (H. annuusL.), ‘Hybrid 894’. The field experiment was conducted on Pullman clay loam (fine, mixed, thermic Torrertic Paleustoll) at Bushland, TX. The 19 perennial genotypes and the commercial sunflower, Hybrid 894, were planted in pure stands. Leaves, stems, and whole plants were evaluated at vegetative, flowering, and fruiting stages to ascertain their nutritive value for ruminants. Crude protein (CP) concentrations of 140 g kg−1and above occurred in leaves of 11 of 19 genotypes at the vegetative stage. Fifteen of the 19 genotypes had whole plant CP of 60 to 90 g kg−1at all stages of maturity. Nutritionally adequate amounts of Ca (2− 8.6 g kg−1) were present in leaves, stems, and whole plants of all genotypes at all stages of maturity. Nutritionally adequate amounts of Mg (1 g kg−1) and K (6.5 g kg−1) were present in leaves and whole plants of most genotypes at all stages of maturity. Leaves, stems, and whole plants of most genotypes had suboptimal P (<2 g kg−1) levels for ruminants at all stages of maturity. Nutritionally adequate amounts of CP, Ca, Mg, and P were present in whole seeds of most genotypes. At varying maturity stages, nutrient levels of some artichoke genotypes are comparable to that of cultivated sunflower. Whether Jerusalem artichoke is mixed with other forbs or grasses in a pasture or hay, or whether it is used as silage, it appears to have the potential to provide a satisfactory nutrition level for ruminants.

Although wild sunflowers (Helianthusspp.) can be components of pastures, hay, and silage, limited information is available on the forage‐quality of sunflower species. The objective of this study was to evaluate wild species of sunflower for protein and mineral concentrations. The experiment had a completely randomized design with three replications. The plots were planted in Pullman clay loam (fine, mixed, thermic Torrertic Palenstolls) soil. The leaves and stems of 26 perennial and one annual wild Helianthusspp., and a commercial annual sunflower hybrid planted in pure stands were evaluated at vegetative, flowering, and fruiting stages to ascertain their nutritive value for ruminants. Crude protein (CP) of 140 g kg−1and above occurred in the leaves of 11 of the 26 perennial species at the vegetative stage. At the flowering stage, only two of the 26 perennial species had CP concentrations above 140 g kg−1in the leaves. Willow‐leaf sunflower (Helianthus salicifoliusDieter) had the highest leaf CP (180 g kg−1) at the vegetative stage. Wild annual sunflower (H. annuusL.) and the commercial ‘Hybrid 894’ had leaf CP concentrations above 140 g kg−1at all stages of maturity. Crude protein concentrations generally declined as plants matured. Crude protein concentrations of seeds were higher in most of the perennial sunflower species than in the wild annual or commercial sunflower. Nutritionally, adequate amounts of Ca (2 to 5 g kg−1), Mg (2 g kg−1), and K (8 g kg−1) were present in the leaves and seed of all wild sunflower species and commercial sunflower. The leaves and stems of all species except the Arizona sunflower (H. arizonensisR. Jackson) had sub‐optimum P levels for high‐producing ruminants. Nutritionally adequate amounts of P (3 g kg−1) were present in seeds of all sunflowers examined. At the vegetative stage, nutrient level of some of the wild perennial sunflowers is comparable to that of cultivated sunflower. Ruminants most likely would not graze pure stands of wild sunflower, but would graze it in mixed stands with other forbs and grasses. The wild sunflower species may also be incorporated in hay or silage and still offer a satisfactory nutrition level.

Although wild sunflower (Helianthusspp.) may be components of pastures, hay, and silage, little information exists on their contribution to overall forage quality. The objective of this study was to evaluate 26 taxa of wild sunflower species for protein and mineral concentrations at various stages of maturity. The field experiment was conducted on Pullman clay loam (fine, mixed, thermic Torrertic Paleustoll) soil, and the experimental design was completely randomized with three replicates. The leaves and stems of 19 annual and seven perennial taxa of wild species and a commercial sunflower, ‘hybrid 894’, were planted in pure stands and evaluated at vegetative, flowering, and fruiting stages to ascertain their nutritive value for ruminants. Crude protein (CP) of 140 g kg−1and above occurred in leaves of 19 of 26 taxa (15 were annuals) at the vegetative stage. Nutritionally adequate amounts of Ca (2 to 5 g kg−1) were present in the leaves and stems of all wild sunflower taxa. Nutritionally adequate amounts of Mg (2 g kg−1) and K (8 g kg−1) were present in the leaves of most wild taxa at all stages of maturity. Leaves and stems of most taxa at the flowering and fruiting stages had sub‐optimum P (< 3 g kg 1) levels for high producing ruminants. Nutritionally adequate amounts of CP, Mg, and P were present in whole seeds of most species. At varying maturity stages, nutrient levels of some of the wild sunflower species are comparable to that of cultivated sunflower. Ruminants most likely would not graze pure stands of wild sunflower but would graze in mixed stands with other forbs and grasses. Hence, wild sunflower may be incorporated into hay or silage and provide a satisfactory nutrition level for ruminants.