670 



EXPERIMENTS IN FORCING AND CROSSING TOMATOES. 



old plants as soon as the last fruit is off will be the best 

 treatment. If it appears earlier, however, spraying with 

 ammoniacal carbonate of copper is to be recommended. 



3. Root-Gall. — Nematode injuries of roots have re- 

 ceived much study of late, and the attention of growers 

 has been called to them in bulletins and in the press. 

 But there are still very few horticulturists who are aware 

 of the extent to which they infest our greenhouses. Many 

 common plants, as geraniums, begonias and coleus, are 

 subject to their attacks, and the diseased plant — or the 

 soil in which it grew — is often dumped into the dirt-bin, 

 where it propagates the trouble. In the southern states 

 the nematodes are serious enemies to many plants in the 

 field, even to trees, but in the north they confine their 

 attention mostly to indoor plants. This 

 indicates that severe frost is fatal to them, 

 and suggests a remedy in the freezing of 

 houses which are seriously attacked, when 

 this can be done to advantage, as between 

 the crops of winter tomatoes. Nematodes 

 are very minute animals belonging to the 

 true worms, and allied to the trichina. 

 These nematodes are a serious menace to 

 tomato-growing under glass. They attack 

 the roots, causing the formation of galls, as 

 in fig. 4. The injury to the root is often 

 much greater than that shown in the illus- 

 tration. Sometimes the whole root is swol- 

 len into one ragged, shapeless mass, strongly 

 reminding one of the club-root of cabbage. p^- ^ 



The trouble is likely to be worst in those 

 plants which are carried over from the preceding winter. 

 In general appearance, plants injured by root-galls are 

 very like those attacked by the winter-blight already de- 

 scribed, save that the leaves do not show a spotted dis- 

 coloration. The plants become weak and stop growing, 

 and the leaves curl and become yellow and dry, much as 

 if the plant were suffering for water. 



The treatment for this disease is to remove the plants 

 and soil, thoroughly wash the benches or boxes with 

 lye, and begin anew. But it would be a great saving of 

 time and expense if the soil could be treated, between 

 the crops, with some material which would destroy the 

 nematodes. This was tried in a small way. Five boxes, 

 each containing four diseased plants, were selected for 

 treatment Decefeber 11, 1891. The plants were removed 

 and the soil was treated as follows; (i.) One-third 

 pound of concentrated commercial lye dissolved in a pail 

 of water. (2.) Two pounds of salt in a pail of water. 

 (3 ) One pound of quick-lime in a pail of water. (4.) Four 

 tablespoonfuls of bisulphide of carbon poured into holes 

 which were quickly closed. (5.) The box placed out- 

 doors and allowed to freeze solid. 



Clean young plants were set in these boxes after the 

 lapse of four or five days, and the boxes were placed side 

 by side in the tomato-house. One or two of the plants 

 died in the soil treated with lye, and the places were re- 

 filled, while three settings had to be made in No. 2^ 

 because of the great amount of salt in the soil. Between 



each setting the salt was washed out by heavy watering. 

 When the plants were removed, six months afterwards, 

 it was found that all contained galls except those in boxes 

 2 and 5 — those salted and frozen — but upon these no galls 

 whatever could be found. The results were definite and 

 satisfactory, but the experiment was too limited to war- 

 rant any general conclusions. They inspire the hope, 

 however, that soils can be treated for nematodes be- 

 tween the forced crops of tomatoes. — L. H. Bailey, in 

 Cornell University Bulletin. 



NOTES FROM THE RURAL GROUNDS. 



Crossing Tomatoes. — The mode of crossing tomatoes 

 is the same as that of crossing potatoes, as the generative 



Common Blight of Tomato. {Cladosponum fulvum). 



organs are much the same in form and arrangement. 

 While, however, it is easy to cross tomatoes because the 

 anthers generally yield more or less pollen, it is difficult 

 to cross potatoes because, in this climate at any rate, the 

 anthers rarely develop pollen. 



Tomatoes sometimes cross naturally. There can be 

 little doubt of it. Hence it is that, now and then, a plant 

 of a given variety bears fruit quite different in color and 

 form from the type ; or leaves of a different color size 

 or incisions. So, too, the habit of plants may differ from 

 the compact form of the "tree-tomato" to the wide- 

 spreading habit of the varieties now in the market, and 

 it is to such variations — not to artificial crossing — that 

 we are indebted for the Acme, Favorite, Perfection, Op- 

 timus, Paragon, and other kinds chiefly in demand at the 

 present time. Professor E. S. Goff gave us a cross be- 

 tween the tree-tomato and the Alpha, and the writer has 

 crossed this cross, but no valuable sort has yet been ob- 

 tained from it. Professor Bailey has hybridized the cur- 

 rant tomato (LycoJ>ersicicm fiimpinellifoliiim) with the 

 common tomato {L. esculentum). Further crosses and 

 selections may lead to nobody knows or may guess what. 

 The writer's work in this line during the past three years 

 leads him to infer that the favorite kinds of the future 

 will depend upon artificially crossing the best varieties 

 of to-day ; by continued careful selection ; and then by 

 further crossing the progeny. 



If we examine a tomato-flower we shall see that the 



