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IOWA ACADEMY OP SCIENCES. 
vicinity of Ames, lowaA® More lhan this, repeated efforts to 
artificially inoculate various varieties of cultivated apples with 
Gymnosporangium macropus have failed. In the spring of 
1886 Dr. Halsted^ inoculated G. macrojnis on two varieties of 
cultivated apple (Rawles’ Janet and Tallman Sweet), wild crab 
Plrus coronaria^^ pear, mountain ash, Pirus semipinnata, 
several species of hawthorn and two forms of Juneberry on the 
grounds of the Iowa Agricultural College, Ames, Iowa. In no 
case did Roestelia appear on the cultivated apples. He says^: 
‘ ‘ The individual experiments numbered among the hundreds, 
and in every case there was a perfect failure of the Gymnos- 
porangium to grow except with the crab apple, where the 
inoculation was most emphatic.” Further inoculations were 
made the following season, 1887. He says^: “During the 
present season cultural experiments with the native cedar have 
been carried out by special students. It is an easy matter to 
inoculate the wild crab with this, but only failures have 
attended tests upon other plants.” In 1893 Prof. L. H. Pam- 
meh made some inoculation experiments at Ames. A tree of 
the variety Tetofsky had been top- worked with Fluke crab, 
which is an 'improved variety of Pirus coronaria; G. macropus 
was inoculated upon both parts of the tree on the same day, 
with the same cedar apple. In due course of time, Roestelia 
appeared in abundance upon the Fluke crab portion of the tree 
but not a single leaf of the Tetofsky portion was affected. 
Inoculations were also made upon pear, Japan quince {Gydonia 
Japonica), cultivated apple and shadbush {AmelancMer alni- 
folia), but these all proved failures. 
The above is, in brief, the history of the experiments at 
Ames previous to 1894. It appears to be well established, that 
at Ames, Iowa, the cultivated apple is wholly exempt from the 
Boestelia disease which is very abundant and destructive in 
New England and in some of the southern states. The Red 
cedar does not grow spontaneously in central Iowa, but it is 
i<x Professor Pammel writes that he has never known or heard of Roestelia on any 
cultivated variety of apple in Iowa. 
2Bulletin of the Iowa Agricultural College, from the Botanical department,. 
November, 1886, pp. 59-64. 
3Bailey considers the wild Pirus of Iowa to be specifically distinct from P. coronaria 
He has named it Pirus lowensis. See L. H. Bailey’s Notes from a Garden Herbarium VI; 
The Soulard crab and its rise. The American Garden, Vol. XII, p. 469. 
4 1. c., p. 63. 
5Bull. from the Bot. Dept, of the Iowa Agricultural College, February, 1888, p. 91. 
^Diseases of foliage and fruit. Report of Iowa State Hort. Soc., Vol. XXVIII, 1893^ 
p. 470. 
