WEED FLORA OF IOWA 



3. Plants not fleshy 4. 

 4. Pistil single 5. 

 5. Flowers regular. 



Stamens numerous, free . . . Ranunculaceae. 

 Stamens numerous; sepals and petals pres- 

 ent, inserted on calyx Rosaceae. 



Stamens 10; fruit a legume. . .Leguminosae. 

 4. Pistil compound 6. 

 6. Ovary free. 



Ovary 1-celled Caryophyllaceae. 



Ovary more than 1-celled 7. 

 7. Ovaries united into a ring. . .Malvaceae. 

 7. Ovaries not united into a ring 8. 

 8. Leaves simple. 



With punctate dots; stamens numer- 

 ous Hypericaceae. 



Leaves not with punctate dots; sta- 

 mens 6 Crwciferae. 



Leaves compound, pinnately 3-foliate. 

 Anacardiaceae. 



Leaflets 3, obcordate Oxalidaceae. 



Leaflets 5-7 pairs Zygophyllaceae. 



Leaflets 3, viscid or fetid herbs 



Capparidaceae. 



6. Ovary adherent; flowers in umbels 



Umbelliferae. 



6. Flowers not in umbels Onagraceae. 



Calyx and corolla present, petals more or less united. 

 2. Flowers regular 3. 



3. Plants with milky juice. 



Stamens united Asclepiadaceae. 



Stamens distinct Apocynaceae. 



3. Plants without milky juice. 



4. Plants twining Convolvulaceae. 



4. Plants not twining 5. 

 5. Stamens 5 or more 6. 



6. Style 2-cleft; flowers not in heads; fruit 



2-4 seedlike nutlets Boraginaceae. 



Fruit many seeded pod. . .Hydrophyllaceae. 

 Flowers in heads; anthers in ring or 



tube about the style Compositae. 



6. Style 1; fruit many seeded Solanaceae. 



5. Stamens fewer than corolla lobes 



Caulescent, flowers blue Yerbenaceae 



Acaulescent, flowers greenish. Plantaginaceae 

 2 Flowers irregular. 



Stems 4-angled; ovary deeply 4-lobed Labiatae. 



Stems not 4-angled; ovary 2-celled. .Scrophulariaceae. 



