A RUST RESISTING CANTALOUPE. 5 
dent that some effective remedy or means of control must be found 
to restore confidence in the melon crop. 
The Cause of the Disease. —The cantaloupe rust or “Blight” 
so called, is the effect of a parasitic fungus which grows and devel¬ 
ops on the tissues of the plant. It has been named “Macros- 
porimn Cucumerinum,” by Ellis and Everhart. It spreads and de¬ 
velops by means of spores that are carried by wind and other 
means and which develop when conditions are favorable. The 
idea that rain and dew cause the rust is true in the same sense that 
rain causes weeds,-it simply affords conditions favorable for devel¬ 
opment. 
Investigations jor Controlling the Disease. —In 1898, H. H. 
Griffin, of the Colorado Experiment Station, began investigations to 
control the disease. He carefully conducted field tests with sprays 
of different fungicides, and Bordeaux mixture gave promise of en¬ 
couraging results, but owing to the rapid growing nature of the 
cantaloupe vines, and the frequency of spraying required, with its 
attendant expense, this plan proved impracticable. 
By a series of tests, it became evident that the disease is not 
communicated by the seed, except as it might occasionally occur 
from spores accidentally lodging with the seed. 
The next step was the development of a resistant strain of can¬ 
taloupes. 
A Rust-resisting Cantaloupe. —In the summer of 1903 a close 
study of the cantaloupe fields was made to ascertain if any varia¬ 
tion existed in the rust resisting tendency of the various strains of 
Rocky Ford cantaloupe. Owing to the different soil conditions 
and cultural methods on different farms, and the varying ages of 
the vines, conclusions were difficult to draw, as all the vines seemed 
to be affected with rust to some extent, and eventually all suc¬ 
cumbed to its attacks, though several growers claimed to have can¬ 
taloupes that did not rust “like their neighbors.” 
In order to make a relative comparison of the point in ques¬ 
tion a small quantity of seed of five of the oldest and most distinct 
strains of seed, was secured from those who were propagating them. 
This seed was planted on a plat of ground that in 1903 had grown 
a very badly rusted crop of cantaloupes; two rows of each kind were 
planted May 9th, 1904, with a row of watermelons separating each 
variety to prevent their vines from intermingling. The whole plat 
had uniform conditions of culture in every particular and the vines 
of each variety made a very similar growth. About Aug. 1st the 
rust began to develop in the center of the hills, and it soon became 
evident that the disease was not making the same progress on all 
plants. Some of the hills in the rows planted with seed fur¬ 
nished by Mr. J. P. Pollock remained green throughout the season, 
