ON PROP A GA TION BY SEED. 213 



germinate till the third or fourth season. If these seeds, instead of 

 being sown immediately after gathering, are dried and sown the same 

 autumn, none will come up till the spring of the second year. This 

 holds good also with the seeds of a number of trees and shrubs, among 

 which may be mentioned daphne, ribes, rubus, rosa, potentilla, berberis, 

 pseonia, &c. De Candolle mentions a sowing of tobacco which con- 

 tinued to send up plants in sufficient numbers to form a crop every 

 year for ten years. It is a common occurrence to find plants, espe- 

 cially annuals, springing up in ground newly brought into cultivation, 

 alter it had been used many years for other purposes. Thus, a field 

 of grass that was ploughed up near Dunkeld in Scotland, after a period 

 of fourteen years in turf, yielded a considerable crop of black oats with- 

 out sowing. Mustard-seed has sprung up in the fern lands, which 

 must have lain there upwards of a century ; and white clover, it is well 

 known to every agriculturist, springs up, on the application of lime in 

 soils, where it had not been before seen in the memory of man. In 

 pulling down old buildings, seeds capable of germinating have been 

 found in the clay used as mortar. The seed of Veronica hederaefolia, 

 L., after heavy rains, has been known to spring up on the surface of 

 fields where previously no trace of that plant was to be found. 



The season for sowing seeds is, in nature, when they are ripe, but in 

 artificial culture it varies according to the object in view. The spring, 

 however, is the most favourable period for germination, because at 

 this season the warmth daily increases, and the vegetable kingdom 

 awakens from the sleep of nature. Seeds removed from foreign 

 countries, and also the seeds of any rare indigenous plant, should be 

 sown as soon as they are removed or gathered, in a soil and situation 

 favourable for germination and growth. For a succession of crops of 

 annual culinary plants, or annual flowers, the gardener sows at different 

 periods ; and in the case of biennial plants, he sows in the autumn. The 

 time of sowing is very much determined by the time that it is desired 

 to reap. It should be noted that all seeds, of whatever kind, should 

 be sown in dry soil, and not watered till they begin to vegetate ; in 

 the case of old or sickly seeds, to water them at the time of sowing is 

 to insure their destruction by rotting ; that shading is to be preferred 

 to watering ; finally, that all seedlings, except bulbs, should be potted 

 or transplanted as soon as they will bear handling. 



The mechanical process of sowing is very simple ; whether the seeds 

 are sown broad-cast, that is, distributed equally over an even surface, 

 or deposited in drills or regular furrows, they are delivered from the 

 hand, or from small hand drills. Some rough seeds, such as those of 

 the carrot, are mixed with sand, to separate them so that they may 

 drop singly ; and other very small seeds, such as those of rhododen- 

 drons, and other ericacese, are mixed with fine sand to prevent them 

 from falling too thickly. The smallest seeds of all, such as those of 

 the ferns, and of some of the hardy orchidese, are sown on the surface 

 of pots or pans filled with well-drained peat and sand, and placed in a 

 shady place and covered with glass. American tree seeds of small size 

 are generally sown in pans or boxes as soon as received, and kept 



