THE BARBERRY IN IOWA 233 



•;andy alluvial bottom. The soil on the banks is a bluish, sticky clay, 

 ,ir of a yellowish color in a few places slightly springy. 



It may be of interest to make a note of the plants found in the 

 region; the Missouri gooseberry (Ribcs gracile) is common and is 

 L^enerally distributed in the area. There was also some Rihcs 

 ['y)iosbatl and Cornus aspcrifolia. The only other shrubs found 

 Kic are Vitis vitlpina, Pscdcra vitacea, RJiits Toxicodendron, 

 Cclasfrus scandens, Xanthoxyhun americanum, Rosa arkansana, 

 Ruhus occidentalis. The following trees were rather common, hack- 

 berry (Ccltis occidentalis) hickory (Carya ovafa) bur oak (Quercus 

 uiacrocarpa), a few red oaks (Q. rubra) and white oak (Q. alba), 

 red haw (Crataegus mollis, C. punctata), elm (Ulinus americana, U. 

 fiihra), ironwood (Ostyra virginiana) , basswood (Tilia americana) , 

 wild crab (Pyrus ioensis), choke cherry (Primus virginiana) , black 

 cherry (P. serotina), hard maple (Acer nigrum), red mulberry 

 (Morus rubra), the Russian mulberry (Morus alba var. Tatarica) 

 (naturalized in several places, came from the Giddings place), black 

 walnut (Juglans nigra). The herbaceous plants noted were the 

 blue violet (Viola cucullata), Sweet William (Phlox divaricata) , 

 columbine (Aquilcgia canadensis), Solidago ulmifolia, Poa pratensis, 

 Plileum pratense, Sanicula marilandica, Smilacina stellata, S. race- 

 mosa, Fragaria virginiana var. illinocnsis, Vicia americana. Aster 

 sagittifoUus, wild cranesbill. Geranium maculatum. The question has 

 sometimes been raised as to whether the soil where the plants 

 establish themselves belongs to the calcareous type. The area near 

 Kelley belongs to the Wisconsin drift soil and while limestone is 

 not in evidence on the surface the soil is not acid but must be 

 classed as one having an abundance of lime. It may be of interest 

 to remark that every clump of barberry examined by the writer con- 

 tained yellow spots, showing infection, and in quite a few cases sper- 

 mogonia were evident and in others full developed secia discharging 

 their spores freely. I found some timothy in the vicinity of the 

 bushes, but the ascial infection, I think, came from the oats some 

 300 feet away and in all probability also from the squirrel tail which 

 was much nearer, some 150 feet away. There were certainly enough 

 £ecia on these barberries to cause a local rust epidemic. 



In a previous paper I gave the approximate number of aecial 

 spores produced at Pocahontas, Iowa. The figures I gave there 

 are perhaps too small. On one plant I counted twelve aecial infected 

 leaves. Miss C. M. King estimated approximately 4,000 spores 

 in one of the ascia. This infected leaf had 48,000 spores. Another 

 badly infected leaf had 120 ascia. On the same basis there were 



