Cropland 



Land that is used regularly for the growing of crops (ex- 

 cept forest crops and permanent pasture). Includes orchards, 

 cultivated summer fallow, rotation pasture, and land that 

 is temporarily idle but customarily used for production of 

 crops. 



Crop Residue 



The parts of plants, or a crop, left in the field after har- 

 vesting the desired part such as grain or fruit, e. g., Stubble. 



Crop Rotation 



The growing of different crops in recurring succession 

 on the same piece of land. 



Crop, Standing 



The total amount of organic material of one or more 

 species in a certain space at a given time; e. g., the trees in 

 a stand that are useful for lumber or other products, cf. 

 Biomass. 



Cross 



See Hybrid. 



Cross-fertilization 



Sexual reproduction by means of two separate organisms, 

 cf. Self-pollination, Cross-pollination. 



Crossing-over 



The interchange of parts of Chromatids (q. v.) of Ho- 

 mologous chromosomes during pairing in Meiosis. 



Cross-pollination 



The transfer of pollen from the anther in the flower of 

 one plant to the stigma in the flower of another plant. Syn. 

 Xenogamy, cf. Self-pollination. 



Cross-timbers 



Strips of oak forest at right angles to the river systems 

 in Oklahoma and Texas. 



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