Imprinting 



A form of rapid and stable learning in a young animal 

 when it is exposed to a meaningful stimulus. 



Inalpage 



The residence of flocks and herds upon Alpages (q. v.). 



Inbreeding 



The mating of closely related organisms, cf. Outbreeding. 



Incompatibility 



A failure or partial failure of some process which results 

 in lack of Fertilization. See Self -incompatibility. 



Increaser 



A plant already present in a community or area which 

 increases in abundance under overgrazing, cf. Decreaser. 



Increment 



The increase in the Basal area (q. v.), diameter, height, 

 volume, quality, or value of a tree or a Stand. 



Increment Borer 



An instrument used for securing from the trunk of a 

 tree a core which shows the Growth rings. 



Indehiscent 



Refers to a structure, especially fruits of plants, that do 

 not break open when ripe. cf. Dehiscent. 



Index, Frequency 



See Frequency index. 



Index of Similarity 



The ratio of the number of species found in common in 

 two communities to the total number of species that are 

 present in both, cf. Coefficient of community. 



Index Species 



An organism that is so well adapted to its habitat it 



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