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Kig. 25. The loose mulch 

 on forest unils. 



Fig. 'JO. The 80II -mulch 

 on tilled Innds. 



€ 



J' 



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Ktfi. 'J7. A liumu uiuUe pliuiker. 



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p: 



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 atMU-tlng 



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1 Ixi TV 



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 roller hm l>o«n u*«d. 



