May 1, 1873. ] 



JOUENAL OP HORTICULTUEE AND COIIACtE GAitDENEE. 



355 



Hoses. — Tea-scented: Gloire do Dijon and Marfobal Niel. 

 Hybrid Perpetuals : Gfant des Batailles, Victor Verdier, 

 Charles Lefebvre, Louise Darzins, Beauty of Waltham, Ba- 

 ronne PrevoBt, La Eeine, Jules Margottin, and Boule de 

 Niege. 



Camellias. — Lady Hume's Blush, Fimbriata, Alba plena, 

 Imbricata, Wilderii, Jubilee, Bealii, Princess Bacchochi, Teu- 

 tonia. Countess of Orkney, and Opiima. 



Geraniums. — i'Vok-Zi, Dr. Andry, Eugene Duval, and Madame 

 Charles Keteleer. SIiow, Celestial, Desdemona, Joan of Arc, 

 Mrs. Hoyle, Queen of Whites, and Etna. Fancy, Ellen Beck, 

 Delicatum, Madame Sainton Dolby, Formosa, ETcning Star, 

 and Cloth of Silver. 



Fuchsias. — Pvose of Castille, Lady Heytesbury, Annie, 

 Minnie Banks, Venus de Medeci, Souvenir de Chiswick, Black 

 Prince, Beauty of Kent, War Eagle, Avalanche, Vaiuqueur de 

 Puebla, and Madame Cornelissen. 



Chrijsanthe77iums. — Pompons, Cedo Nulli, Bob, Lizzie 

 Holmes, Duruflet, Golden Cedo Nulli, Aurora BoreaUs, Bril- 

 liant, Bijou de Horticulture, White Trevenna, General Can- 

 robert, Sainte Thais, and Surprise. Lart]e-floioered, Dr. Sharpe, 

 Julie Lagravere, Lady Slade, Princess of Wales, Little Harry, 

 Golden Beverley, White Globe, Jardin des Plants, Empress of 

 Lidia, Mr. Bruulees, Jewess, and John Salter. Japanese or 

 late-flowering, Eed Dragon, Wizard, James Salter, and Hero 

 of Magdala. 



Ferns. — Adiantum cuneatum, formosnm, and trapeziforme, 

 Asplenium bulbiterum and lucidum, Cyrtomium falcatum, 

 Doodia caudata, Nephrodium uiolle, Pteris serrulata, serrulata 

 cristata, longifolia, and tremula. A few of the greenhouse 

 SelagineUas may be introduced, such as Selagiuella denticu- 

 lata, braziliensis, as well as S. Martensii and stolonifera. 



Variegated-foliayed Plants. — Aralia Sieboldii variegata, Far- 

 fugium grande, Dracaana Veitchii, Osmanthus ilicifolius varie- 

 gatus, Bambusa Fortunei variegata. Yucca aloifolia variegata, 

 Abutilon Thompsoni, Coronilla glauca variegata, Agapanthus 

 umbellatus variegatus. Variegated Myrtle, Hydrangea varie- 

 gata, Arnndo Donax variegata. 



The Chrysanthemums will not require your greenhouse till 

 the autumn ; your cold frames will grow them for the present, 

 afterwards grow themout-doois.) 



THE POTATO DISEASE. 



Answers to Circular addressed to Cultivators of Potatoes in 

 the Counties of Boss, cC-c. By Colonel J. A. Grant, C.B. 

 With Remarks hy Professor Church and Dr. Hooker. In- 

 verness : Printed for Private Circulation, 1873. 



The Potato Disease : Its Cause and Remedy. By Samuel 

 Smith, M.E.C.S.E., &c. London: Smith & Allen, 1873. 



Who was the " Man in the Iron Mask ?" Who wrote " The 

 Letters of Junius?" What causes the Potato disease? are 

 questions that have exercised the ingenuity of many minds, 

 but each has defied the inquirer. Leaving the question of the 

 disease's cause, our own conclusion, after reading nearly all 

 that has been written on the subject, and after many years of 

 experience in Potato culture, is this : — Whole large sets of the 

 earliest ripening varieties planted very early on a light soil 

 resting on a gravelly subsoil, and manured for the previous 

 crop only, usually afford Potatoes not affected by the disease. 



The disease itselE we consider is a gangrene of the tuber, a 

 gangrene that affords a fitting nourishment for the parasitic 

 fungus which hastens and completes the destruction of the 

 tuber. 



Colonel Grant's is by far the most trustworthy publication 

 we have ever met with on the subject. He sent a circular con- 

 taining twenty-eight queries to one hundred cultivators of the 

 Potato in Scotland, and had from them fifty-five replies. The 

 queries asked for a statement of the soil, drainage, elevation, 

 aspect, manure used, varieties least diseased, when and what 

 part was first affected, time of appearance, \veather, protection, 

 &c. Col. Grant gives this as the 



" Summary of the Fifty-five Replies. 



" Soil. — Light sandy loam upon gravel subsoil has proved to 

 be the best soil, and di-y moss probably stands next. It should 

 be well worked up in autumn, manured with suitable manure, 

 and left exposed in high drills during frost. In early spring it 

 should be well cleaned, manured with vegetable ashes (potash), 

 burnt earth, hme, guano, or artificial manure, according to the 

 soil, and no animals nor carts allowed to trample it down. 



" Seed. — The best specimens of the tuber should be used as 

 seed. They should be kept in a dry weU-veutilated place, where 



the temperature was not above 48", and not below 35°. They 

 ought to be of a kind which has not been introduced above 

 twenty years, and of a variety which is known to bear fruit 

 (plums). Before planting, the seed should be fumigated with 

 sulphur smoke or dipped in the solution previously given, so as 

 to destroy all trace of fungus upon its surface. The cattle 

 might be fed with all diseased ones, as they relish them, or the 

 fowls would eat them boiled. This is preferable far than allow- 

 ing them to reproduce a hereditary disease. 



" The haulms contain the disease, and if they are carried to a 

 Potato field as manure, they communicate the germs to the 

 coming crop, but their ashes would fertilise the soil. Several 

 East Lothian farmers, in their able reports, write that they had 

 remarkable Wheat crops from the fields where they had not 

 raised their diseased Potatoes ; but this is owing, probably, to 

 the soil not having been exhausted rather than to diseased Pota- 

 toes being a superior manure, and, in principle, I am incUned to 

 condemn strongly such a process of planting the germs of a 

 disease. Upon tliis subject we have the advantage of an ex- 

 perienced chemist's opinion — Professor Church — who writes me, 

 ' I think we may say that the disease could not be conveyed to 

 the next crop, say of Wheat, nor to the Potatoes succeeding in 

 the fourth or eighth year of the rotation, by ploughing-in the 

 diseased tubers, &c. But indirectly it might do some harm by 

 increasing the organic matter in certain sods, and in such cases, 

 perhaps, burning everything that could be collected would be 

 better. Often the Potatoes this year (1872) have been too rotten 

 to be lifted at all. Possibly, if "the crop were ploughed-in, and 

 next-year Potatoes grown in a contiguous field, there might be 

 some danger of theu' continuing the descent of the fungus.' 



" Time of Planting. — Some have a preference to planting late 

 in autumn, saying the frost would not harm the seed ; and I am 

 rather in favour of this, as the soil would act as a deodoriser to 

 any existing fungus. But the main thing is to have fresh red- 

 tinted seed, producing dark green haulms ; to plant so early that 

 plums would be formed by the time the disease season generally 

 reached the farm, and never to hft till all the sap in the haulms 

 has descended into the tubers. 



" Mode of Planting. — Wide apart, and upon the surface of the 

 soil. 



" Manure. — There are as many kinds of manure as there are of 

 soils and opinions upon both. The returns in question 6 show 

 this ; and without the time of planting, the quality and nature 

 of the. seed and soU, state of the field, amount of rainfall, and 

 other causes only known to the farmer himself, it is impossible, 

 without laboratory work, as Professor Church writes me, to give 

 any particular Potato manure. But I have no doubt that a 

 beneficial manure may be selected from the column of farm and 

 artificial manures under question 0." 



Professor Church, Eoyal Agricultural College, Cirencester, 

 after analysing the replies and observing ' ' they do not throw 

 any startling fight on the subject," derives from them these 

 conclusions : — 



"The fulfilment of the following conditions conduces to the 

 health of the Potato and its resistance to the murrain : — 



1. Good drainage. 



2. A porous but fertile soU. 



3. Free circulation of air above and within the soU. 



4. The selection of sound and perfectly healthy tubers (not 



too small) for sets. 



5. The choice of new and early varieties of the Potato. 



6. Where the land is heavy and wet, planting the sets on, and 



not helow, the general level. 



7. The use of artificial manures, such as kainite, nitrate of 



soda, and superphosphate, with small quantities only of 

 farmyard manure, upon wet lands rich in organic matter. 



8. The free use of ashes, including birrnt earth, leaves, 



weeds, &c. 



9. Earthing-up, so as to spread out rather than crowd the 



haulms together. 

 10. Eemoving the haulms entirely if diseased badly, then sow- 

 ing soot and lime, &c., broadcast. If rain does not follow, 

 then rolling the field." 



Dr. Hooker briefly replies — 



" I cannot say that I can glean any definite practical conclu- 

 sions from the replies which are likely to be useful to farmers. 



" It cannot be doubted, after the study the subject has re- 

 ceived both here and upon the Continent, that the disease is 

 due to the attack of a microscopic fungus, the development of 

 which is greatly facilitated by warm wet weather, such as we 

 had last year (1872). 



" The conclusion at which you arrive at the end of para- 

 graph 17, appears to me to indicate the most reasonable chance 

 of escaping the consequences of this scourge for the future. If 

 we could get new kinds of Potatoes which would ripen not later 

 than the beginning of July we should be safe." 



Mr. Smith's is a very small pamphlet. He does not think 

 the fungus, Peronospora infestans, constitutes the disease, but 



