Table 2. The identity and percentage of pollen collected by honey bees over a 16-week period.
| Plant family |
% of pollen over 16 weeks |
Plant genus/species | Common name | ||
|---|---|---|---|---|---|
| Site 1 | Site 2 | Site 3 | |||
| Fabaceae* | 5.97 | 1.38 | 0.84 | G. max | Soybean |
| 3.98 | — | 0.14 | Lotus corniculatus | Common bird's-foot-trefoil | |
| 6.91 | 0.59 | 0.52 | Melilotus sp. | Sweet clover | |
| . | 0.02 | 0.82 | Trifolium campestre | Hop clover | |
| 5.45 | 0.35 | 0.54 | Trifolium hybridum | Alsike clover | |
| 0.04 | 16.39 | 14.79 | Trifolium pratense | Red clover | |
| 2.02 | 15.84 | 10.35 | Trifolium repens | White clover | |
| 4.13 | — | 3.46 | Trifolium sp. | Unknown clover | |
| 8.24 | 1.18 | — | — | NA | |
| — | 0.02 | — | — | Tufted vetch | |
| Brassicaceae* | 12.62 | 6.12 | 4.89 | Unknown (likely including S. arvensis) | Mustards and cabbages |
| Asteraceae | 0.83 | 8.3 | 6.8 | Ambrosia artemisiifolia | Common ragweed |
| . | 0.02 | 0.02 | Arctium minus | Wild rhubarb | |
| 0.5 | 0.13 | 1.68 | Cichorium intybus | Common chicory | |
| — | — | — | Cirsium sp. | Plume thistle | |
| — | — | — | Helianthus sp. | Sunflower | |
| 2.21 | 1.31 | 0.88 | Solidago sp. | Goldenrod | |
| — | 0.04 | 0.07 | Taraxacum officinale | Common dandelion | |
| 0.08 | 3.19 | 3.76 | Unknown | NA | |
| Vitaceae | 6.91 | 8 | 1.86 | Vitis sp. | Wild grape |
| Plantaginaceae | 6.66 | 7.14 | 10.99 | Plantago sp. | Fleawort |
| Euphorbiaceae | 0.1 | 6.6 | 9.67 | Mercurialis sp. | Spurges |
| Rosaceae* | 0.02 | — | — | Crataegus sp. | Hawthorn |
| — | — | — | Malus sp. | Apple | |
| 0.04 | – | — | — | Cinquefoils | |
| 0.04 | – | — | — | Plum, cherry, peach group | |
| 3 | 0.2 | — | — | Chokecherry | |
| 0.06 | 0.02 | 0.14 | Rubus sp. | Blackberry group | |
| 3.48 | 0.09 | . | Unknown | NA | |
| Adoxaceae | 6.49 | 3.34 | 6.03 | Sambucus sp. | Elderberry |
| Araliaceae | 4.92 | — | — | Aralia sp. | Spikenard |
| Cyperaceae | 3.42 | 0.04 | — | Carex sp. | Sedges |
| Unknown (P7A-50 #4) | 0.17 | 5.96 | 4.26 | Unknown | NA |
| Poaceae* | 0.06 | 2.77 | 3.87 | Zea mays | Maize |
| Umbelliferae* | 3.07 | 1.22 | 2.27 | Unknown | Carrot, celery, parsley group |
| Caprifoliaceae | 2.8 | 0.02 | 0.02 | Lonicera sp. | Honeysuckle |
| — | 0.04 | 0.16 | Diervilla sp. | Bush honeysuckle | |
| Unknown (1-5 apertures) | 1.15 | 0.79 | 0.73 | Unknown | NA |
| Oxalidaceae | 0.04 | 2.56 | 0.02 | Oxalis sp. | Wood sorrel |
| Hypericaceae | 1.04 | 0.22 | 0.82 | Hypericum sp. | St. John's wort |
| Liliaceae | 0.54 | 1.7 | 0.41 | Unknown | Lily family |
| Anacardiaceae | 0.13 | 0.81 | 2.02 | Rhus typhina | Staghorn sumac |
| Ranunculaceae | 0.98 | — | — | — | Columbine |
| — | 0.02 | — | — | NA | |
| Cornaceae | 0.06 | 0.92 | 0.73 | Cornus stolonifera | Red-osier dogwood |
| Salicaceae | 0.02 | 0.68 | 0.07 | Populus sp. | Poplar, aspen, cottonwood |
| 0.1 | — | 1.7 | Salix sp. | Willow | |
| Rhamnaceae | 0.02 | 0.02 | 1.5 | Rhamnus sp. | Buckthorn |
| Amaranthaceae | 0.65 | 0.35 | 0.18 | Chenopodium sp. | Goosefoot |
| Gramineae | 0.38 | 0.31 | — | Unknown | True grasses |
| Malvaceae | 0.31 | — | 0.02 | Tilia sp. | Basswood |
| Balsaminaceae | 0.25 | 0.15 | 0.2 | Impatiens capensis | Common jewelweed |
| Unknown (P7A-16 #4) | 0.08 | — | — | Unknown | NA |
| Betulaceae | — | 0.35 | 0.27 | Corylus sp. | Hazel |
| Caryophyllaceae | — | 0.31 | — | Unknown | Carnation family |
| Unknown (P7A-29 #6) | — | 0.22 | — | Unknown | NA |
| Unknown (P7A-28 #7) | — | 0.17 | — | Unknown | NA |
| Unknown (P7A-47 #9) | — | 0.09 | 0.2 | Unknown | NA |
| Unknown (P7A-47 #8) | — | — | 0.2 | Unknown | NA |
| Unknown (P7A-41 #14) | — | — | 0.11 | Unknown | NA |
| Nymphaeaceae | — | — | 0.07 | Nuphar sp. | Water lily |
| Polygonaceae | — | — | 0.05 | Rumex sp. | Knotweed |
Honey bee hives were placed at one of three sites: (1) in a non-agricultural area (n=28 plant families), (2) adjacent to a maize field grown from untreated seeds (n=30 plant families) or (3) adjacent to a maize field grown from pesticide-treated seeds (n=29 plant families). Note: Asterisks denote plant families that do or may include cultivated plant species. Dashes denote that pollen from a particular plant family was not observed in honey bee pollen loads.