THE EOSE AND ITS CULTURE. 



337 



considered, the same conditions produce identical 

 results in similar localities with so much rapidity, 

 that it generally over-runs a garden or house in a 

 few days after its first appearance. Nor is it to be 

 wondered at, for the air is probably filled with 

 myriads oi spores of the fungus called mildew, and 

 these are ready to fasten upon any plant that is in a 

 condition to afitord them a proper nidus for their 

 establishment and growth. It is a common saying, 

 confirmed by observation, that severe and sudden 

 checks produce mildew, and probably the chief 

 cause of this is a slight exudation of their fluids 

 on the pervious surfaces of their tender leaves and 

 shootlets. On these prepared surfaces the spores 

 faU, obtain a foothold on the saccharine bases, and 

 speedily develop the perfect mildew, rendering the 

 leaves and shootlets as white as a sheet. In this 

 state it develops more spores, that replenish the air 

 with seeds, which seem able to retain their vitality 

 for months— perhaps years — and bide their time for 

 suitable growing-fields, when they arrive. Three 

 conditions or more seem needful for the growth of 

 mildew : vital spores, which are probably always pre- 

 sent, a prepared seed-bed — that is, leaf or stem — and 

 a genial atmosphere. The first and the last are very 

 much beyond our power, but the seed-bed we can 

 control to some extent. First of all, protect leaf and 

 stem from the very appearance of honey-dew, and as 

 far as possible by care and culture against extremes 

 of drought, moisture, heat, cold, weakness, and luxu- 

 riance. It is also of great importance that the root 

 and top should be, as nearly as may be, forced to grow 

 under parallel conditions ; for example, the roots 

 must not be parched while the tops are drenched by 

 rain, nor vice versa,. Should the roots be too low or 

 too wet, they must be lifted. All this to prevent 

 mildew. 



The first step towards the cure of mildew is 

 prompt treatment ; the moment that a leaf is seen 

 whitened in part with mildew, pick it off and then 

 dust the entire tree over with dry sulphur powder 

 through a fine dredge. Some use sulphur vivum 

 instead of the above, or mixed with it ; but powdered 

 sulphur, as fine as it can be made, passing it through 

 a mortar if necessary to insure its being fine, and 

 applied as dry as it can be made by sun or fire- 

 heat without the risk of ignition, is best, and most 

 easily applied. If out of doors, apply the sulphur 

 in the early morning or late at night, when the 

 Roses are dewed over. If there is no dew, spray 

 them over only, then dust and leave the sulphur on 

 for a day or two before washing off. Should any 

 mildew reappear, dust again in a few days, and so 

 on, till the fungus ceases. Sulphur is the only sui-e 

 and certain cure, and unless the mildew has its seat 

 in the unfavourable conditions of the Rose, it sel- 



70 



dom or never fails to speedily arrest, or altogether 

 cure, this troublesome pest. 



Some gardeners prefer applying the sulphur in a 

 liquid state, at the rate of a pound to a gallon of 

 water, and an ounce of black soap, the whole boiled 

 for haK an hour, thoroughly mixed, then another 

 gallon of water added to it, and the leaves and 

 shoots dipped in the mixture, or the same carefully 

 syringed over the affected parts. But the liquid is 

 no more effective than the dry sulphur, and it is 

 besides more difiicult to apply and ruinous to the 

 appearance of the Roses. 



Red Rust or Orange Fungus. — This is a far 

 worse disease than the mildew ; it is not only that 

 the colour is different, but the destructive force and 

 the mode of attack. The white mildew spreads itself 

 with about equal thickness over the entire surface of 

 the leaf or boughs attacked ; the red rust gathers 

 itself together into little heaps, each centre forming 

 the nucleus of fresh colonies, and thus it distributes 

 itself with an energy and rapidity almost unknown 

 to any other pest or disease of the Rose. This and 

 mildew, and almost aU the ills Roses and other 

 plants are heir to, used to be called blight, and the 

 term is most expressive in regard to the red rust or 

 orange fungus, for so rapidly does it spread that the 

 fairest, cleanest, sweetest Rosary of to-day may be 

 utterly ruined or blasted and marred with red rust 

 the day after to-morrow. Its effect on the trees is 

 also most disastrous ; its touch seems to paralyse 

 their vital force, and to an alarming and disastrous 

 extent confuse and derange their vital functions. 

 The functions of the leaves are deranged, their ver- 

 dure lost in huge patches of brownish-red, their 

 free growth is arrested, the flowers dwindle in size, 

 the plant droops into weakness, disease, or death. 



Comparatively little is known about the origin of 

 red rust or orange fungus. It certainly is not be- 

 gotten of cold, as many affirm to be the case with 

 mildew. On the contrary, it mostly appears during 

 or immediately after a spell of hot, dry weather, of 

 shorter or longer duration. Plants also the most 

 fully exposed to the full force of the sun suffer most 

 from red rust. Hybrid Perpetuals too are, as a 

 rule, more subject to it than Teas, Noisettes, 

 climbing, or other Roses. So much is this the case 

 that the writer has never seen red rust on an Ayr- 

 shire, Boursault, or Banksian, or common China 

 Rose. But these facts are given as data for the 

 future rather than guides for the present. 



Unfortunately we have but little to offer in 

 regard to modes of prevention or cure of this dis- 

 ease. Heavy root waterings and surface mulchings 

 in drj' weather have proved the best antidotes against 

 this most dire disease. The choice of a Rosary 



