202 IOWA ACADEMY OF SCIENCE Vol. XXVI, 191 



the barberry are attacked liy a fungus which growing inside of th- 

 leaf-tissues soon breaks out through the epidermis and form 

 numerous very minute yellow cup-like cavities ; hence this has beei 

 called the barberry cluster-cup or barberry rust. 



"When these spores fall out and are blown away, those whic'i 

 alight upon leaves of wheat, oats or barley germinate and soon pene 

 trate the leaf -tissues (the leaf rust was then considered identicc 

 with stem rust) growing there parasitically. This growth in th 

 grain leaf is very rapid in hot damp weather, and in a short spac 

 of time it produces myriads of orange red spores just beneath th 

 epidermis, which they soon break, thus forming the well known re 

 rust patches too common on our small grain nearly every season. 



"The peculiarity in this case of the first stage of the parasit 

 occurring upon another plant has made many doubt the correctne; 

 of DeBary's conclusion that the cluster-cup of the barberry w.' 

 identical with the rust of grain. How soon the study of allied forn 

 appears to indicate the truth of DeBary's conclusion. I have litt' 

 doubt that we shall find that not only the cluster-cups of the ba 

 berry, but that one or more native plants as well produce the ru 

 of our grains. 



"Two remedies or rather preventives will suggest themselves ' 

 every thinking person. The general destruction of the cluster-ci 

 bearing plants would reduce greatly the disease. This, however, 

 not as yet possible. The destruction of the black spores by burnir 

 or otherwise would be an efifective preventive if generally done. Tl 

 thorough burning of the stubble soon after, harvest, and the bun 

 ing or thorough composting of all rusted straw would if dor 

 throughout wide acres of territory, prove effective." 



LETTERS FROM NURSERYMEN IN REGARD TO THE EARLY INTR 

 DUCTION OF THE BARBERRY 



During the fall I sent letters concerning the early planting of tl 

 barberry in Iowa to some of the older nurserymen in the stat 

 Mr. M. J. Wragg wrote me as follows. "My father commence 

 growing the barberry vulgaris which was then called the Canadia 

 barberry, about the year 1870. 



"We grew a great many thousand of these because they wei 

 widely lauded as a plant for making a good hedge for guardin 

 purposes. Along in later years, possibly about the early eighties, tl 



