Glossary. 221 



Greenhouse. A glass house in which plants are grown. 



Originally and properly, however, it was applied to houses 



in which plants were simply preserved green during the 



winter. 



Ha-ha. A sunken fence. 

 Half-breed. A cross between varieties of the same species ; 



cross-breed, mongrel, variety-hybrid. 

 Half-hardy (adj.). A term applied to plants which need 



protection during winter, but which can endure some frost. 

 Half-hybrid. The product of a cross between a species 



and a variety of another species. 

 Hand-box. A box of size sufficient to cover a hill of 



plants, provided with a cover of glass, cloth, or paper, used 



to force plants in the hill. 



Hardiness. Capability to endure a given climate. 

 Hardy (adj.). Able to withstand a given climate. 

 Heart-wood. The inner and colored wood of trees. The 



deeper color and greater hardness of heart-wood are due 



chiefly to the deposition of mineral matter in the cells. 

 Herb. A plant possessing but a small amount of hard, 



woody fibre, the stem of which dies at the approach of winter. 

 Hei barium. A collection of preserved plants. The plants 



are usually dried and glued on sheets of paper. 

 Heeling-in. The process and operation of temporarily 



covering the roots of plants to preserve them until wanted 



for permanent planting. 

 Horticulture. The art and science of raising fruits, 



kitchen garden vegetables, flowers and ornamental trees and 



shrubs. 



Horticulturist. One who practices horticulture. 

 Hot-bed. A frame covered with glass, cloth or paper, 



provided with bottom heat, and used for forcing plants. 

 Hot-house. A glass house, artificially warmed, in which 



plants are grown. 



