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This table shows that the ammonia-bordeaux gave the least number of live leaves and the potash-bordeaux next, with two checks occupying a middle position in the scale, and exceeded by the Bordeaux and the soda-bordeaux. These figures, while they give the rate of maturing of the foliage, do not prove to be an index of the amount of rust upon the plants.

To determine the relative rustiness of the foliage the following plan was adopted: The worst five rusty leaves were selected from the five best plants, and from these five the average leaf was taken in each section. Upon these the pustules (sori) of the rust were counted with the following results in terms of pustules per square inch of leaf surface:

From this table it may be seen that all of the fungicides were active in keeping down the number of spore spots. Upon the leaves receiving the ammonia-bordeaux almost no rust made its appearance, while with the soda-bordeaux the amount was less than a sixth that shown by the average of the checks. There was but a trifle of difference between the results with the Bordeaux and the potashbordeaux, there being less than an eighth of that shown upon the checks.

No satisfactory results were obtained in the attempt to check the stem blight (Phlyctœna), and this accounts for the apparent discrepancy between the two tables of results above shown. In short, the stem blight attacked the plants indiscriminately, and thus made serious inroads upon a plant whether it was rusted or not, sometimes breaking it down prematurely.

Figure 42 shows six sunflower leaves with the effects of four fungicides upon the rust. In Figure 43 is given a larger view of a leaf sprayed with the potash-bordeaux along with one from a check section of the experiment row of sunflowers.