1902.] PUBLIC DOCUMENT — No. 33. 71 



other conditions being equal, to remain vigorous during 

 seasons of drought. AVhen the asparagus rust first made its 

 appearance, tliere could be seen beds in which one portion 

 was infected, while the other showed not the slightest trace 

 of disease. The only dift'erences existing in the plants were 

 in their ajje and treatment. The dift'erences of infection in 

 these cases were due to dificreut degrees of vigor. But 

 such beds, being in regions where the soil is very sandy, 

 subso(|uently became rusted. One bed on the college ground 

 has had the fall stage since 1890, it usually appearing be- 

 tween September 15 and October 1. It has, however, never 

 shown any trace of the rust in summer, or previous to 

 September. Other beds, both young and old, situated close 

 by, have been entirely free at times, and only insignificant 

 teleuto spore pustules have been found on them very late in 

 the fall. All the beds are situated on soils possessing high 

 water-retaining properties, as well as an abundant supply of 

 water from below. 



Some attention was given to the rust problem by this 

 division during the summer, and many localities have been 

 examined. We have also, as usual, sent out a series of 

 circulars, asking for information on certain points. Among 

 other questions asked were those relating to the effect of dew, 

 elevation and sliclter from tree growths, etc., on infection. 

 Not a single instance has been brought to our attention 

 where the shelter produced by forest growths or crops has 

 exerted any influence. As to the eflcct of elevation, con- 

 siderable diflerences have ahvays been observed by us in the 

 amount of rust on a single bed, and such instances have 

 been reported by asparagus growers in their correspondence. 

 Where a bed runs down a little elevation, and where there 

 are more moisture and organic matter contained in the soil, 

 the plants are larger, more luxuriant, and there is less 

 infection. No grower has been able to give us the slightest 

 hint that plants are prone to show more infection in regions 

 that are subject to dews. Since there is likely to be more 

 dew deposited on the lower part of a bed than on the upper 

 part of it, and if this factor is alone responsible for infection, 

 we would expect to find more rust on those i)lants grown on 

 the low portions of the bed than on the upper part. This is, 



