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COOPERATIVE OBSERVATIONS UPON RUSTS OF CEREALS.

It is with the hope of interesting more persons in the investigation of the rusts, and of being able to place before the public other feets concerning these diseases than are possible to individuals working apparately, that I ask, for the coming season, the cooperative observations and reports of fellow investigators upon the following general points:

1. Has the mycelium of any or all of the following rusts:
Puccinia graminis. P. Rubigo-vera. or P. coronata succeeded in passing the winter alive in the tissues of their hosts, in your locality?

2. During what months of the past autumn and winter have you noticed uredospore pustules forming upon winter cereals? What species of rusts?

3. Note date in spring when first new pustules of uredospores are undoubtedly forming upon new plants. In other words, when there are some indications that the disease is spreading from plant to plant by means of the uredospores. In this connection kindly note: (a) mean daily temperature, (b) if possible, atmospheric humidity, (c) species of rusts

4. Note date of general infection of wheat and oats.
By general infection is meant that time (usually occupying from two to three days between the time of flowering and ripening) at which red rust seems to become general throughout a given locality. In connection with this, kindly note: (a) the direction of the prevailing winds for three or four days during first period of general infection, (b) mean daily temperature, and (c) if possible, the atmospheric humidity, (d) the host plant and the species of rust. (If there is doubt concerning the rust, a specimen will gladly be received and determined).

5. Miscellania: Any notes regarding rusts of cereals--vitality of uredospores, mode of first infection of host, etc.

At the close of the season the facts sollated from these cooperative reports, together with my own investigations, will be carefully edited and published in bulletin form, due credit being given to all.

Yours respectfully,
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