56 



Popular Science Monthly 



days the manure is taken down to the beds and less fragile than the first, and the gray, 

 where it is carefully heaped in ridges along This last has a rich odor, but the deep color 



galleries with rough walls. Small acquired at a late stage of growth 



bricks or "leaves" of mushroom ^ --.,^^^ lowers its price in the markets. 



spawn are inserted in holes ^^ ^\ The "sets" of spawn intro- 



made in the ridges. The 

 growth of this spawn, 

 called by botanists 

 ' 'mycelium, ' ' is checked 

 by dryness and quick- 

 ened by humidity and 

 heat. The spawn throws 

 out threads which 

 spread in all directions 

 and finally fill the entire 

 ridge of manure. 



Mushrooms Require As 

 Much Care As a Baby 



The skill of the cul- 

 tivator reveals itself 

 in adjusting local con- 

 ditions to the require- 

 ments' of his beds. 

 The chief difficulty arises from the enor- 

 mous amount of air absorbed by mush- 

 rooms. They die of suffocation easily. Not 

 only must the galleries be thoroughly ven- 

 tilated, but the air must be moist and 

 changes of temperature must be avoided. 

 Verily, young mushrooms are frail. 



The three kinds grown in the under- 

 ground beds around Paris are: the white, 

 which is small and delicate in flavor but 

 does not bear transportation well; the 

 light yellow — stronger, more productive 



Entrance to a subterranean mushroom 

 bed near Paris. In many places aban- 

 doned quarries are utilized in this way 



duced into the manure de- 

 generate after a while, 

 so that raisers seldom 

 cultivate from one 

 seeding more than two 

 or three years. They 

 prefer to take fresh 

 spawn obtained by 

 scientific methods 

 which allow a selection 

 of mushrooms, and 

 then to reproduce the 

 best by direct germ- 

 ination of the spores. 



There are in the De- . 

 partment of the Seine 

 two hundred and fifty 

 mushroom-beds, some 

 of great extent, owned 

 by eighty proprietors; the annual value of 

 the yield near Paris is about $2,500,000. 

 Other vegetable growths also receive 

 subterranean cultivation both in other parts 

 of France and elsewhere. French and 

 Belgian market gardeners grow certain 

 vegetables out of season and blanch them 

 underground, one of the most curious exam- 

 ples of the method being the cultivation of 

 wild chicory, a form of endive. Celery 

 and plants of similar nature are also grown 

 and blanched underground. 



Cutting potato sprouts with pruning shears after three weeks of growth in the underground 

 molds. About three months later the potatoes are large enough to be marketed 



