TERMS IN FORESTRY. 13 



Future yield. The amount of wood which given trees upon a given area will con- 

 tain after a given period. 



Future yield table. A tabular statement of future yield. 



(xreen pruning*. See Pruning. 



(rround cover. All small plants growing in a foi-est, except young trees; such as 

 ferns, mosses, grasses, and weeds. See Underbrush. 

 G., Bode'ndecke. F., couverture du sol. 



(xround fire. See Forest fire. 



(xroui) method. A method of conservative lumbering in which groups of young 

 trees which have sprung up in openings caused by logging, insect damage, wind- 

 fall, snowbreak, or other agency, are taken as starting points for the future forest; 

 or if these are insufficient, small openings are purposely made. Reproduction by 

 self-sown seed from the mature stand at the edges of these groups is secured by 

 careful cuttings, which extend the groups until they join. See Forest management. 

 Syn. : group system, shelterwood group system. G., Horst und gruppenweise 

 Verjiingung, Gruppenwirtschaft. 



Group mixture. A mixed forest in which trees of the same species occur in groups 

 not large enough to be considered pure stands. 



Group seed method. A method of conservative lumbering in which the forest is 

 reproduced after a single cutting, by leaving in groups seed trees of the kind desired. 

 See Forest management. 



Group system. See Group method. 



Growing" stock. See Stand. 



Hahit, n. See Silvics. 



Harden oif, to. To prepare seedlings in the seedbed for transplanting by gradually 

 exposing them to wind and sunlight. 



Heel in, to. To store young trees for planting by laying them against the side of a 

 trench and covering the roots with earth. 



Heig"ht class. All trees in a stand whose heights are within prescribed limits. 

 G., Hohenklasse. F., classe de hauteur. 



Height g"rowth. The increase in height of a tree. 

 G., Hohenwuchs. F., croissance en hauteur. 



Heig'ht measure. An instrument for measuring the height of a tree. 

 Syn.: hypsometer. G., Hohenmesser. F., dendrometre. 



Hi^h forest. See Seed forest. 



Hig^h forest compartment system. See Stand method. 



High or seedling" forest system. See Seed system. 



Hig-h pole. See Pole. 



Hill planting. /See Mound planting. 



Humus, n. That portion of the forest floor in which decomposition is well advanced. 

 Syn.: mold. G. and F., Humus. 



Hypsometer, w. See Height measure. 



Improvement cutting. See Improvement thinning. 



Improvement thinning. Usually the first thinning made when a forest is put 

 under management, to prepare it for the application of a regular system. See 

 Thinning. 



Syn.: improvement cutting, preliminary thinning. G., Verbesserungshieb. F., 

 coupe d'amelioration. 



Income rotation. See Rotation. 



