82 



IRISH GARDENING. 



it is to keep a look out for the first appearance 

 of this fungus, and when discovered to carefully 

 dig up the affected plants before the final rotting- 

 stage is reached, and dur?i them. This he would 

 do to prevent the infection of the soil. 



The roots of all transplanted Brassica should 

 be examined, and if clubbed (as they frequently 

 are) they should on no account be planted, but 

 destroyed by fire. Bought plant particularly 

 should be examined to prevent the introduction 

 of the disease into gardens free from its infection. 

 It should also be remembered that cruciferous 

 weeds, such as shepherd's purse, and flowers, 

 such as wall-flowers and stocks, are also liable 

 to the disease. 



Once a soil gets badly infected it is a most 

 difficult matter to effect a remedy. One plan is 

 to stop cropping it with cruciferous plants for 

 several years, the idea being that the spores will 

 gradually die out for lack of a suitable host. 

 But this course does not always result in success, 

 as the spores seem to have very great powers 

 of resistance. 



The best remedy yet discovered, perhaps, is 

 quick-lime. One reason for this appears to be 

 that the fungus seems to thrive best in an acid 

 soil, and soils frequently and heavily manured 

 with dung are often acid. Quick-lime, as every- 

 one knows, corrects acidity, and a heavy dress- 

 ing will do more than neutralise the acid — it will 

 render the soil alkaline, and alkalinity is unfavour- 

 able to the success of the club-root fungus. 

 But the lime must be freshly burnt and in a 

 caustic condition when applied to the soil. It 

 must be applied immediately after the removal of 

 the diseased crop, and it must be thoroughly 

 worked into the soil so as to secure its universal 

 distribution throughout its mass. 



Swellings are frequently seen on the base of 

 the stems of cabbages and Brussels sprouts, and 

 on the upper part of the " root " (which is really 

 the lower part of the stem) of the turnip. These 

 lumps are often spoken of as "club-root," but 

 they are not caused by a fungus at all. They 

 are more of the nature of galls, and are caused 

 by a particular kind of beetle. The beetle pierces 

 a hole in the stem and lays an Q.gg there ; this 

 Q^gg hatches out into a grub, the presence of 

 which causes the irritation that induces the forma- 

 tion of the gall. In time the grub bores a hole 

 to the surface and escapes. But this is "another 



story." 



^* ^* e^* 



Rosemary. — The common Rosemary is a well-known 

 plant in old gardens. Rosemary tea infused from its 

 leaves is an old-lime remedy. A prostrate variety 

 (Rosmarinus officinalis prostratus) was distributed some 

 years ago by Mr. Smith of Newry. It is well suited 

 for rockery work ; its slender sprays, furnished with 

 pointed leaves, hang- gracefully over the stones, and 

 form a very pleasing sight, especially when carrying its 

 pretty little purplish lilac flowers. It can be propagated 

 by cuttings. 



Artificial Manures : 



Or, " Back to the Land." 



By JOHN -W. McKay, A.R.C.S.I., Instructor in Agriculture for 

 the County of Dublin. 



THAT plants require a number of sub- 

 stances to enable them to reach full 

 development, and that of these sub- 

 stances they are most likely to find difficulty 

 in obtaining the requisite supply of nitrogen, 

 phosphates and potash, is now generally re- 

 cognised,* the cause being the steady removal 

 of these materials from the soil in various ways ; 

 all crops remove them to a greater or less 

 extent ; then drainage water is further re- 

 sponsible ior considerable loss, and in the case 

 of nitrogen a portion passes into the air when 

 animal or vegetable matter rots, but, with the 

 latter exception, the soluble part of these sub- 

 stances is ultimately carried to the sea, and 

 would appear to be lost. Nature's policy seems 

 to be to allow of no waste and to turn every- 

 thing to useful account, and therefore it is 

 likely that some provision will be made for the 

 preservation and eventual replacement of these 

 materials. 



If this be so, how are they again recovered? 

 We find the answer to this in the large natural 

 supplies of materials which, when treated by 

 processes more or less simple, are used by 

 cultivators of the soil for replacing its lost 

 fertility, and are known by the general descrip- 

 tion, "artificial manures." This term conveys 

 an erroneous idea to the minds of many, who 

 imagine that the substances referred to are 

 unnatural and unsuitable as supplies of food 

 for plants. A consideration of the source of 

 these "artificials" will, however, serve to dis- 

 pel any ideas of the kind. 



On many of the rocky uninhabited islands off 

 the coasts of South America and Africa in- 

 numerable sea birds congregate for breeding 

 purposes, and as the rainfall is small in those 

 districts the droppings of these birds, together 

 with the bones and other remains of fish on 

 which they feed, and eventually their own 

 carcases, have been accumulating for ages. 

 When these deposits are partly decayed and 



* See " Manuring of Crops," p. 50, in April number of 

 Irish Gardening. 



