346 



OHIO EXPERIMENT STATION: BULLETIN 175. 



234 Climbing Milkweed (P) Gonolobus Icevis Michx. Is a climbing-, long- 

 stemmed plant with opposite, heart-shaped, pointed leaves and pods and seeds 

 as in the other milkweeds. The flowers are very small and inconspicuous, 

 while the leaves are 3 to 5 inches wide. It is a very troublesome and unsightl}' 

 weed along- fence-rows near the Ohio river, from Brown county westward. 

 Seeds much as in the common milkweed. Climbing milkweed offers good reason 

 for cleaning out fences, after which it will yet require continued cutting and 

 salting or cultivation. 



MORNING-GLORY FAMILY, CONVOLVULACE.E. 



235 Man=of=the= Earth, Wild Potato=vine (P) Ipomceapandurata (L.) Meyer. 

 As an example of food storage in large, thick roots this 

 man-of-the-earth, Fig. 42, can scarcely be surpassed. The 

 leaves are long pointed and sometimes fiddle-shaped, the 

 flowers larger than those of the morning-glory, with purple 

 eye (center) and roots very large. Halsted has found some 

 single roots weighing 35 pounds. These are of various 

 forms, often club-shaped, thick and fleshy, two or more feet 

 long, spreading chiefly underground. An enduring pest in 

 sandy or rocky soils, where deep in the earth or in the 

 cavities among the rocks it survives many years. The leaves 

 are attacked by a white mold, Cystopus Ipomcece-pandurance 

 (S.), which infests others of this group, including the 

 sweet potato. 



Mere occasional cutting will not destroy it and digging 

 out the root is too expensive, even where possible, which it 

 is not, among rocks. The best available method for starv- 

 ing out these large roots is repeated treatment with hoe 

 and salt or with sulfuric acid; salt is generally more convenient and safer. 



236 Field Morning=glory (A) *Ipomcea hederacea Jacq. This morning- 

 glory is found in fields generally. It resembles the cultivated sorts which also 

 grow in fields but often has halberd-shaped leaves. It is attacked by the fungus 

 above named. 



Seeds dark, angular, 

 resembling those of culti- 

 vated varieties. Destroyed 

 by pulling before seeding. 



237 Field Bindweed 

 (P) * Convolvulus atvensis 

 L. The field bindweed, or 

 small flowered morning- 

 glory, is a somewhat re- 

 cently imported pest of the 

 most serious sort. The 

 character of the weed may 

 be seen from the illustra- 

 tion, Fig. 43. The leaves 

 and the small flowers, 1 

 inch or less in diameter at 

 the top, are certain char- 

 acters of recognition. It 

 grows with stems several 

 feet in length, twining a- 

 boilt themselves or about 



any other plants, which 



FlG. 43. Field Bindweed. 



Fig. 42. Man-of-the- 

 Earth. 



(After Millspaugh.) 



