58 



THE GARDENER'S MONTHLY 



[February, 



SCRAPS AND QUERIES. 



Fruiting of the Maiden Hair Tree. — Mr. B, 

 Landreth writes : " In the report of a meeting of 

 the Academy of Natural Sciences in the Phila- 

 delphia North American, I read that Mr. 

 Meehan referred to some seeds of the Salisburia, 

 or Ginko biloba, from a tree growing on the 

 grounds of C. J. Wister, in Germantown, and 

 stated that they were probably the first pro- 

 duced in the United States. The plant has been 

 considered strictly dioecious, but the fact that 

 these seeds were borne by a tree at Germantown, 

 there being no flowering specimens nearer than 

 Woodlands, would indicate that the commonly 

 received opinion is not correct. The subject of 

 the sexes of plants was further considered, and 

 evidence was advanced to support the opinion 

 that distinctions of groups in coniferse, founded 

 upon sexual characters were not of much value. 



''I have noticed the above paragraph respecting 

 the seeding of the Salisburia, and take pleasure 

 in informing you that the largest tree at Blooms- 

 dale has produced fruit since 1871 — ten years ; 

 the past season fully a peck. There is no 

 other tree that I know of for miles near it." 



Evolution of Heat in Plants.—" D. P. F.," 

 Hanover, York Co., Pa., asks : "Can you tell me 

 where to find any information in regard to the 

 evolution of heat in tlie growth of plants? Is 

 there much heat evolved and is this in propor- 

 tion to the amount of growth and vigor or not?" 



[We do not think there has been much written 

 anywhere about this subject, except what has 

 appeared from time to time in the pages of our 

 magazine. 



We have taught in our pages that in all vital 

 action, equally in the vegetable as in the animal 

 kingdom, the evolution of heat is an attribute 

 of life. In other words the decomposition of 

 food is essential to life, and heat is evolved by 

 this decomposition. That there is a specific de- 

 gree of heat in plants is proved in various ways. 

 For instance, if a maple tree be subject to sev- 

 eral weeks temperature, say of near zero, and 

 suddenly the temperature rises to 38°, the sap 

 will run out in streams from a cut branch, and, 

 during the night following icicles often form a 

 foot long. If there were not a specific degree of 

 heat in plants the juices of the tree would freeze 

 solid, and it would take days to thaw when pro- 

 tected as it is by non-conducting bark. The sap 



could not run out freely, immediately the tem- 

 perature of the atmosphere rose above the freez- 

 ing point. 



Again, a very good illustration of the way in 

 which a plant can hold its heat in spite of exter- 

 nal influences may be seen on a warm day 

 towards spring, when the leaves and fences are 

 covered by thawing snow. The steam will arise 

 under the warm sun, from corn stalks, dead 

 leaves, or dead wood in fences, but not from 

 living leaves. The dead matter readily receives 

 heat from the sun— the living plant resists heat 

 as readily as it resists cold. A living tree seems 

 cool to the hand in hot days, when a dead tree 

 or a post is warm. 



Sometimes we find parts of plants warmer at 

 times than at others, and especially when they 

 have a great deal of work to do — just as we find 

 to be the case in animals. It has been found 

 that when a palm or a large flowered aroid is 

 about to open its blossoms a thermometer thrust 

 into its spathe will show a temperature of 80°, 

 while the external air may be but 70°. This 

 shows that plants have some specific heat. 



Just what this is, however, so far as we know, 

 has never been determined. What has been 

 ascertained is chiefly in the direction we have 

 here outlined, and may be reduced to little more 

 than this, that life in plants and life in animals 

 in its relation to heat is substantially the same. 

 —Ed. G. M.l 



Bauanas from Seed. — " D. B. W.," Crockett's 

 Bluff, Arkansas, writes : " You say ' it is gener- 

 allj^ known that the ordinary banana never pro- 

 duces seed.' ' The fruit is a pulpy seed vessel, 

 but the seeds never perfect.' I can hardly think 

 this entirely correct. There must be some place 

 where this plant perfects seeds, else where do 

 the varieties come from ? I have found instances 

 of individual plants of a polygamous species, 

 like the persimmon or grape, that produced fine 

 fruit containing no seeds, but had supposed that 

 all plants that produce what are commonly 

 termed fruits also produced, at least some of the 

 plants of the same species, perfect seeds. I be' 

 lieve we have plants that flower but give no 

 seeds ; also plants that neither flower nor pro- 

 duce seeds. For instance we have a rank grow- 

 ing three-sided and very common sedge in the 

 Illinois river swamps that produces neither seeds 

 nor blossoms. I am also informed that the 

 'cane' of the Southern 'cane-brakes' neither flow- 

 ers nor seeds ; also the ' sugar cane.' The sweet 



