516 



PRACTICE OF GARDENING. 



Part III. 



by decay, and separation of the dust by sifting with new tan. In this, way the bark-bed is 

 obliged to be stirred, turned, refreshed, or even renewed several times a year, so as to 

 produce and retain at all times a bottom heat of from 75 to 85 degrees in each of the 

 three departments of pine culture. These operations being common, we have placed a 

 summary of management under the head of General Directions for the Bark-pit, at the end 

 of this section. (See Subsect. 8.) 



2708. Dung-heat. Pines are grown to the greatest perfection by many gardeners with- 

 out either bark or fire heat simply by the use of dung. A frame double the usual depth 

 and also about a third part broader than the common cucumber frames, is placed on a bed 

 of dung, or of dung and tan, or dung and ashes, or even dung and faggots mixed or in 

 alternate layers. This bed of itself supplies heat for a while, and when it begins to be 

 exhausted, linings are applied in the usual way, and continued for a year or more, reviv- 

 ing and renewing them as may become requisite, till the bottom bed becomes too solid 

 for the ready admission of heat. The frame and pots are then removed to a prepared bed, 

 and this old bottom taken away, or mixed up with fresh materials. In this way, as 

 Weeks observes, every one that can procure stable-dung may grow pines. In a tract 

 On the Ananas and on Melons, by A. Taylor, printed in 1769, the author tells us 

 that he both rears and fruits pines in a pit formed of boards or of brick-work three 

 feet deep, and of any convenient length and width ; and on the walls or boards which 

 enclose the tan, he places a frame two and a half feet deep in front, and four feet high 

 behind. The ends and front are of glass, and the latter is formed into small sashes, 

 which slide in a groove. The back is formed of inch boards ; and against these he places 

 a powerful lining of dung. The pit he fills with tan, or dung, as may be most convenient ; 

 " dung," he says, " does as well as tan and only requires a little more trouble, which is 

 amply repaid to the gardener by the value of the dung to the garden, when no longer in 

 active fermentation. " An anonymous annotator (to the copy of Taylor's book, in the library 

 of the Horticultural Society) says, " I find by experience, that the dung of four horses is 

 sufficient to work two frames twenty-six feet each in length, and six in breadth ; one for the 

 fruiting-house, the other for succession plants ; and that it may be reasonably expected to 

 cut forty fruit yearly after the first year, and that dung as valuable for the field or garden, 

 as if this use had not been made of it." (Taylor on Ananas, &c. p. 3. ; Diff. Modes of 

 Cult. P. App.&c. p. 47.) 



2709- Fire-heat for the atmosphere. The high temperature requisite for the pine in 

 every stage of its growth, renders it necessary to have recourse to fire-heat for eight or 

 nine months in <every year ; unless indeed the plants are grown in pits heated by linings 

 of dung ; in which case, these linings become necessary every month in the year in order 

 to keep up the bottom heat. What respects the management of fires being also common 

 to the culture of this plant in all its stages, we have placed the directions as in the case 

 of bark-pits under such as are general. (See Subsect. 8.) 



2710. Dung-heat and fire-heat com- 

 bined. Jenkins, of the Portman nur- 

 sery, London, grows his pine-plants in 

 large hot-beds, and fruits them in a 

 house (fig. 454.), which " though fur. 

 nished with flues, yet these have been 

 very little used. The heat imparted to 

 the plants is produced by the ferment 

 ation of stable-dung in a pit below the 

 plants, the top of which is covered by 

 tiles supported by iron rafters, with the 

 joints closely cemented, to prevent the 

 passage of steam into the house. The 

 pots are neither bedded in tan, nor in 

 mould, but stand on the tiles, and the 

 interstices between them warm the air of 

 the house." The dung is managed as in 

 "West's pit, but with the addition of being 

 watered after it is thrown in, which is 

 found to promote fermentation, and the 

 intensity of the heat. (Hooker, in Hart. 

 Trans, iv. 363.) 



2711. Steam-heat, with or without any of the other modes of heating, has been tried 

 extensively as far as respects heating the air of the house, and with the most perfect suc- 

 cess. As a bottom heat it has also been tried in different places by turning it into vaults 

 of air, or cisterns of water, or chambers of large rough stones (which imbibe the heat and 

 give it slowly out to the bed above) with different degrees of success, but not such as to 

 induce cultivators to relinquish fermenting substances in its favor, where they can be 

 procured at a reasonable expense. 



Subsect. 4. Propagation of the Pine-apple. 



2712. The pine is generally propagated by crowns and suckers, though, in common with 

 every other plant, it may be propagated by seed. Speedily prefers suckers, because ge- 



