18 Composition and Nutritive Value of Straw. 



General Composition. 



Water 13'70 



Soluble organic matter 8'04 



Soluble inorganic matter 2*76 



Insoluble organic matter 72*84 



Insoluble mineral matter ". 2-66 



n i. i j n * 100-00 



Detailed Composition. 



Water 13*70 



Oil 1-69 



* Albumen and other soluble protein compounds '44 



Mucilage, extractive matters (soluble in water) 7-60 



Digestible fibre, &c .. 29-27 



Soluble inorganic matter 2'76 



f Insoluble protein compounds 2-31 



Indigestible woody fibre 39'57 



Insoluble inorganic matter 2*66 



100-00 



""Containing nitrogen .. .. '07 



fContaining nitrogen -37 



Total percentage of nitrogen '44 



Equal to protein compounds 2*75 



Total ash 5-42 



On burning, oat-straw leaves on an average 5 to 5J per cent, 

 of ash, which has the following composition : 



Ash of Oat-straw. 



Potash 19-14 



Soda 9-09 



Magnesia 3'78 



Lime 8-07 



Phosphoric acid 2-56 



Sulphuric acid 3-26 



Silica 48-42 



Peroxide of iron .. . 1*83 



Chloride of sodium 3'25 



100-00 



Like all the ashes of the straw of cereal crops, oat-straw contains 

 a large proportion of silica, and but little phosphoric acid. 



It will be seen that oat-straw contains about as much oil, and 

 the same proportion of albuminous compounds, as wheat-straw. 

 There are, however, some remarkable differences between them ; 

 for in oat-straw at least in the specimen analysed there is 

 much more sugar and other soluble matter than in wheat-straw. 

 It likewise appears that the crude woody fibre of the former is 

 more easily attacked by dilute alkalies and acids ; so that by this 

 treatment 29 per cent, of digestible fibre was obtained, and the 

 indigestible fibre was reduced to 30J per cent ; whilst in wheat- 

 straw no less than 54 per cent, of woody fibre was found to be 



