114 



to whether it is not the same as wheat rust or some other dreaded rust. 

 Fortunately this rust is not the same as wheat rust, however much it 

 may to the ordinary observer appear to resemble it. Confined as it is 

 in its attacks to the white clover, it does little harm. In other 

 countries it attacks red clover, but I believe there is no record of such 

 a case in this country. 



It is unnecessary to enter upon any discussion of remedies, as the 

 disease is of no serious consequence. It would not receive attention 

 here but for the fact that it is sometimes forwarded by needlessly 



Fig. 127. Uredo-spore and teleuto-spore of the rust-fungus, Vromyces tnfolii 

 (Alb. and Schw.), of the Common White Clover. 



Uredo-spores. The scattered cinnamon brown sori bear roundish or ellipsoidal 

 pale brown echinulate spores, measuring 25-35 x 15-18 ^ each possessed of two 

 opposite equatorial germ pores. 



Teleuto-spores. The sori are darker than those of the uredo-spore stage and 

 bear more nearly spherical smooth dark-brown spores of a diameter varying 

 between 20 and 35 A*> and each having a large germ pore at the thickened apex, 

 where there is often one or more papillae. 



alarmed correspondents. No uneasiness need be caused by the 

 appearance of rust on white clover. 



Oat Rust. 



On one occasion my inquiries on this subject covered a considerable 

 area devoted to dairying on the Tweed and Eichmond Eivers, for the 

 most part consisting of lands similar to that in the vicinity of the 

 town of Alstonville. A score or more of paddocks in a dozen or more 

 localities were examined both as to the amount of rust and the 

 nature of the rust. I found that the paddocks in the vicinity of the 

 settlements were, as a rule, more severely smitten with rust than 

 paddocks elsewhere. Thus I found considerable rust in paddocks 

 in the vicinity of Lismore, Murwillumbah and Alstonville. In 

 general the amount of rust seen was not such as to cause surprise or 

 even concern. As a rule, I found the oat crops comparatively free 

 from this disease. No doubt the larger amount to be seen in certain 

 paddocks near the towns was accounted for by the continuous growth 

 of oats in those paddocks or near by. Under such circumstances the 

 disease is bound to accumulate. The continuous growth of any crop for 

 a long series of years on the same land always has this result. Though 

 at first the diseases of the crop may be light their intensity increases 

 year by year. A little thought will show that this is only what must 

 be expected, not only with crops of oats, but with any crop, or any 

 class of stock. Thus the comparative freedom of new clearings from 

 rust is in accordance with this law. It does not of course follow that 

 a new paddock may not be severely smitten with rust. Such a thing 

 may occur, but in the natural course of events this will be less common 

 than a similar visitation on an old paddock that has borne oats for a 

 succession of years. In the course of my inquiries I had my attention 



