CONVOLVULACEAE 



CONVOLVULUS FAMILY 



COMMON DODDER. LOVE VINE 



Cuscuta Gronovii Willd. 



The Dodders, several kinds of which are in Illinois, are 

 familiar examples of parasitic seed plants. They twine and feed 

 on other plants and lack chlorophyll, being yellowish instead. 



Their seeds germinate on 

 soil, usually rather late in spring 

 after other vegetation has 

 sprouted and young shoots of 

 host plants are thus available. 

 The yoimg shoot of a Dodder is 

 a fine yellow threadlike struc- 

 ture whose tip rotates as it 

 elongates. If it fails to contact 

 a host it lives but a few weeks at 

 most. However, if it finds a suit- 

 able host it grows vigorously, 

 twining about the host and at 

 the same time penetrating it 

 with absorbing organs that really 

 are modified roots. Soon the 

 Dodder loses all connection with 

 the soil and becomes purely a 

 parasite. 



Some Dodders may grow on 

 various hosts, while others are 

 restricted to a certain kind. In 

 Europe they are destructive to 

 crops such as Clover and Flax, 

 and in America probably less so. 



In the southern third of Illinois Dodders are a common pest 

 on Clover. 



The Common Dodder or Love Vine grows on various kinds of 

 herbs and low shrubs from Nova Scotia to Manitoba and south 

 to Florida and Texas. 



It blooms in July and August. Calyx and corolla are 5-lobed 

 and on the inside of the corolla are 5 toothed scales. There are 

 5 stamens and a pistil with a 2-celled ovary and 2 styles. The 

 fruit is a small whitish capsule containing 1-4 seeds. 



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