ASCLEPIADORA VIRIDIS IN OHIO. 



Robert F. Griggs. 



While collecting spiders on the upland in the vicinity of 

 Cantwell Cliff, in Hocking County, Ohio, Mr. W. M. Barrows 

 noticed a peculiar appearing milkweed which he brought in to 

 camp and turned over to the writer. Upon examination it 

 proves to be Asclepiadora viridis (Walt) A. Or. This is a 

 southern plant listed as occurring from "Illinois to Kansas, 

 Texas, South Carohna and Florida." It will be observed that 

 the distribution as given is somewhat unusual, for most plants 

 occurring both in Illinois and South Carolina also range further 

 north in the east as well as across the southern states, following 

 more or less typically Merriam's Carolinian area. The uplands 

 on which it occurred have been found to harbor numerous other 

 southern plants not known to occur within more than a hundred 

 miles of the Sugar Grove area of which the present station is a 

 part. Notable among these are Viola hirsutiila, Eupatorium 

 rotundifoUum and Eupatoriun aromaticun, which are abundant 

 in some stations on the upland. The fact that only a single 

 plant of Asclepiadora was found might be taken to indicate 

 that it has been introduced in cultural operations, but when the 

 habits of the milkweeds are taken into account it is seen that 

 its solitary occurrence does not necessarily throw doubt on its 

 nativity for several of the rarer milkweeds in our area (Asclepias 

 Sullivantii, A. amplexicaulis and A. variegata) have been found 

 only once or twice, although the district has been collected over 

 rather thoroughly for a number of years. While there is not, 

 therefore, sufficient basis for a positive assertion that the plant 

 is native, that appears to be a more likely hypothesis, than that 

 it is introduced. If this is to be accepted as the most likely 

 supposition, its occurrence in the Sugar Grove area is a rather 

 notable extension of its range. 



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