738 



TheWeekly Florists' Review* 



APRIL IT. 1902. 



days, and the fruits will appear. These 

 are the conditions which suit the "rot" or 

 "drop fungus" (Selerotinia Libertiana). 

 J. W. N. has probably allowed his soil to 

 become dry, either between crops or in 

 the first stages of growth of ths crop. 



The second point to consider is that 

 of heat. In the short, dark days of win- 

 ter the temperature at night should never 

 rise above 4.5 degrees, for even if this 

 fungus is present it is never very active 

 at a low temperature. We have at this 

 station a solid bed used in crop rotation, 

 which has nevsr had the soil changed 

 since being planted in this, the cool 

 compartment of the greenhouse, in the 

 fall of 189S. It is never, only for a few- 

 days at a time, without some sort of a 

 crop, and the fertility is kept up with 

 manur.^ and commercial fertilizers. The 

 crops grown are, first, chrysanthemums; 

 second, lettuce ; third, radishes and beets ; 

 fourth, encumbers. These cover the whole 

 year, and, of course, the soil is always 

 in a moist condition. This year instead 

 of bsets and radishes we have grown a 

 second crop of lettuce, which is about 

 to mature, and not a sign of the "drop" 

 disease to be seen. 



The only disease which is ever trouble- 

 some is a burning of the tips of the 

 leaves, upon which, if the conditions are 

 right, the spores of Botrytis vulgaris 

 will grow, and possibly ruin the entire 

 plant. Weather conditions and inactiv- 

 ity of the roots are responsible for this. 

 At first we imagined the plants had been 

 kept too wet, and we had batter with- 

 hold water; but this made matters worse, 

 and we now make no change, but give 

 plenty of water at all times. Lettuce are 



tion. I would like to make use of the 

 pipes and also have them under bench, 

 out of the way. The house is 50x91-2, 7 

 feet high in center, 3V2 feet wall (2 feet 

 in ground, leaving 1\2 feet above 

 ground). Ends are partly glass. Houses 

 run east and west. House No. 2 is laid 

 with -l-inch boiler flues, 2 flows and 4 re- 

 turns, and this gives good satisfaction. 

 Night temperature 60 degrees. House 

 SOxlSi/v. ft., 8 ft. high. Joins the dwell- 

 ing house on east side. Sash bars 10 ft. 

 to the south, the north side being of 

 lumber, except 4 lights in the roof, each 

 3x5ft. 



■ 1 want to add on the north side of this 

 house a new house for growing chrysan- 

 themums and lettuce, and probably car- 

 nations, if necessary, by dividing the 

 house. Want to use solid beds if ad- 

 visable. I have 3-inch boiler flues to 

 heat with. How shall I place them if I 

 have solid beds? 



I have a No. 15 Hitchings corrugated 

 boiler. Will it be large enough to heat 

 all three houses? C. J. L. 



In reply to the several inquiries of C. 

 J. L., the difficulties with the heating of 

 the No. 1 house, in which he uses 1-inch 

 pipes arranged in zig-zag coils, is caused 

 very largely by the excessive friction in 

 these small pipes and the long travel of 

 the water necessitated by the form of 

 coils he uses; then, in order to make 

 matters worse, in the No. 2 house, which 

 is nearer the boiler, he uses 4-inch pipes 

 for coils, thus giving the house nearest 

 the boiler every advantage over the one 

 furthest from the boiler, allowing the 

 circulation to take the shortest cut and 



B- 



■n 



MRVfANE 



yVAtMS 



Plan. HOUSEJO'>9' 



aT'COS or3-l" PfCi fACH 





-4 



BrNCH 



J- f/'f^e ^i-o-. 



^-hHeiunNj 



5lOE Elemotion 



Piping Suggested to C. J. L. 



very thirsty plants, their broad Isaves 

 giving off immense quantities of water 

 on bright days. 



As a further proof of the inability of 

 some fungi to grow in a cool, moist 

 place, we have a mushroom bed upon 

 one end of which a faucet has leaked 

 considerable water. In this spot there 

 is no sign of a mushroom, while in the 

 other part of the bed, subject to the 

 right conditions, the "buttons" are com- 

 ing right along. Thos. H. White, 



Gardener Md. Agr. Exp. Sta.. 



College Park, Md. 



PIPING. 



How shall I arrange the pipes in my 

 carnation house to realize the best re- 

 sults? The flow and return to the house 

 are 32 feet li/i-inch pipe. From there 

 it divides into four coils, each coil of 1- 

 inch pipe, with 6 pipes hanging on bench 

 in the walk. It does not give satisfac- 



that which otfers the least resistance. If 

 it is desired to utilize the 1-inch pipes, 

 which he has in house No. 1, he can do 

 so by changing the form of the coils 

 from the zig-zag to a two-tier coil, as 

 indicated in the accompanying plan, and 

 it would also be advisable to change the 

 size of the main leading from the boiler 

 from 114-inch to 2-ineh. 



Regarding the proposed No. 3 house, 

 he does not say what width he desires to 

 make it ; therefore, I cannot advise him 

 as to the pipe arrangement; but as he 

 has 3-inch tubes on hand which he wishes 

 to use, he can do so by using one line of 

 tubes to every 34 inches of glass con- 

 tained in the roof, measuring across the 

 roof from gutter to gutter. 



Regarding the capacity of the boiler, 

 he has to heat an additional house, it 

 has very little surplus of capacity over 

 this present work, and he should not put 

 on it more than 250 sq. ft. of additional 

 glass, unless he is willing to do consid- 



erable night firing in very cold weather. 



In placing the pipes in No. 3 house, if 

 he decides to use solid beds it would be 

 a good plan to place a flow pipe right at 

 the eaves above the bench and bring the 

 return back in the walk on the side of the 

 bench. 



New York. Henry W. Gibbons. 



PIPING AND BOILERS. 



In reply to the inquiry of P. N., the 

 little base-burning boiler would not have 

 capacity suflicieut to heat the two carna- 

 tion houses he describes. The No. 15 

 boiler would have more than sufficient 

 capacity for the rose and propagating 

 house; but even if the two boilers were 

 connected together their combined heat- 

 ing capacity would bo somewhat scant 

 for the economical heating of the entire 

 range; but if first cost is a serious con- 

 sideration, they could, with some addi- 

 tional care and a little forcing in coldest 

 weather, be made to heat the two houses. 

 It would, however, be more satisfactory 

 to discard the smaller boiler and substi- 

 tute a new surface-burning boiler of 

 larger capacity, as the base-burning boiler 

 is not as economical in fuel as would 

 be the surface burner. 



The floor of the boiler pit should not 

 be less than 7 feet below tha floor of 

 the greenhouses, in order to give good 

 results. The heating pipes within the 

 house should have a rise from tha boiler 

 end to the opposite end of not less than 

 4 inches. I am assuming that there is 

 glass on the roof of tliese houses only, as 

 P. N. does not show anything to indi- 

 cate glass on the side walls; and if such 

 b3 the case, he should use not less than 

 4 lines of the 4-inch pipes he has on 

 hand in each of the carnation houses, 7 

 or even 8 in the rose house and 2 in the 

 propagating house. 



The chimney should have a height of 

 not less than 16 feet above the floor 

 level of the greenhouses; its flue should 

 be 12 inches square, surrounded by 8 

 inches of brick wall. 



New York. Hexrt W. Gibbons. 



THRIPS INJURIOUS IN GREEN- 

 HOUSES. 



By F. H. Chittenden. 

 Asalsi.inl Entomologist. U. S. Dept. Agriculture 



Most florists are acquainted with 

 "thrips," but it may not be generally 

 known that there are several species of 

 these little creatures which do more or 

 less injury to plants grown under glass. 

 The commonest and most destructive spe- 

 cies in America are generally known un- 

 der the name of onion thrips, greenhouse 

 thrips and strawberry thrips. 



All of the thrips are exceedingly min- 

 ute, and the species mentioned do not, 

 even in their largest forms— the females 

 — exceed one-twentieth of an inch in 

 length. They have elongate bodies, and 

 the mature or winged forms have four 

 very slender wings fringed with long, 

 delicate hairs, which gives the insect the 

 appearance shown at figure 1 a. These 

 insects are somewhat anomalous in the 

 manner of their feeding. Their moufh- 

 parts are both fitted for sucking and bit- 

 ing, on account of which they form an 

 order by themselves, the Physopoda, in- 

 termediate between the true sucking and 

 the biting or chewing insects. 



Thrips of one or more species are to 

 be found in most of our common flow- 

 ers, and it is seldom that roses and the 

 blossoms of clover, daisy, and various 



