Pulverized limestone (fine-ground limestone) is the product obtained by 

 grinding either calcareous or dolomitic limestone so that all the material will pass 

 a 20-mesh sieve and at least seventy-five per cent (75%) will pass a 100-mesh sieve. 



Secondary fertilizer components are those other than the "primary fertilizer 

 components" that are essential to the proper growth of plants and that may be 

 needed by some soils. Some of these components are calcium, magnesium, sulfur 

 manganese, copper, zinc, and boron. 



A unit of plant food is twenty (20) pounds, or one per cent (1%) of a ton. 



Waste lime, by-product lime, is any industrial waste or by-product contain- 

 ing calcium or calcium and magnesium in forms that will neutralize acids. It may 

 be designated by the prefixation of the name of the industry or process by which 

 it is produced, i.e., gas-house lime, tanners' lime, acetylene lime-waste, lime-kiln 

 ashes, calcium silicate, etc. 



Interpretations 



The term "lime" shall not be used in the registration, labelling, or guarantee- 

 ing of fertilizers or fertilizing materials unless the lime is in a form or forms to 

 neutralize soil acidity. 



The weights appearing on packages of fertilizer, agricultural lime, and liming 

 materials shall always mean net weights. 



