394 



IOWA ACADEMY OF SCIENCE 



Stick-tight 94 



Stink Grass 8 



Stoneseed 67 



Stramonium 73 



Sunflower, Wild 92 



Sweet Clover 49 



Taraxacum officinale 110 



Teasel, Wild 80 



Thistle, Bull 104 



Thistle, Canada 105 



Thistle, Common 104 



Thistle, Sow Ill 



Thorn-apple 73 



Thorough Wort 82 



Tickle Grass 2 



Timothy 6 



Toadflax 76 



Touch-me-not, Spotted 54 



Tragopogon porrifolius 108 



Tragopogon pratensis 109 



Trefoil, Yellow 51 



Trifolium hybridum 48 



Trifolium pratense 46 



Trifolium repens 47 



Trumpet Weed 81 



Tumble Weed 26 



Tussilago Farfara 100 



Velvet Leaf 55 



Verbascum Blattaria 75 



Verbascum Thapsus 74 



Verbena hastata 69 



Verbena urticaefolium 68 



Vervain, Blue 69 



Vervain, Nettle-leaved 68 



Virginia Knot-weed 18 



Wheat Thief 67 



White Marsh Bent Grass 7 



Wild Buckwheat 19 



Wild Carrot 61 



Wormwood, Roman 87 



Xanthium canadensis 88 



Xanthium spinosum 89 



Yarrow 96 



