ABSTRACT
T h i s i s a response paper t o D. E. G l o t f e l t y ' s "The E f fec ts o f Conservat ion T i l l a g e P r a c t i c e s on P e s t i c i d e V o l a t i l i z a t i o n and Degradat ion" (Chapter 9). Tha t r e p o r t p r o v i d e s a genera l r e v i e w o f how c o n s e r v a t i o n t i l l a g e p r a c t i c e s a f f e c t s o i l p r o p e r t i e s and, i n tu rn , how these changes may a f f e c t p e s t i c i d e d i s s i p a t i o n . The impact o f t i l l a g e management on p e s t i c i d e uptake by p l a n t s was n o t discussed. T h i s response paper p rov ides some research examples o f how t i l l a g e has a f f e c t e d s o i l p r o p e r t i e s and p e s t i c i d e pers is tence . The s t u d y o f both was n o t t h e o b j e c t i v e o f most i n v e s t i g a t i o n s , so cause and e f f e c t o f t e n must be i n f e r r e d . Ma jo r emphasis (and most resource i n f o r m a t i o n ) i s on comparing n o - t i l l w i t h conven t iona l moldboard p low t i l l a g e s i n c e t h e n o - t i l l rep resen ts t h e extreme case o f v a r i o u s forms o f c o n s e r v a t i o n t i l l a g e p r a c t i c e s . It shou ld be recognized, however, t h a t im te rmed ia te forms o f conserva t ion t i l l a g e , e.g., mulch t i l l and r i d g e till, may more n e a r l y resemble conven t iona l t i l l a g e w i t h r e s p e c t t o s o i l p h y s i c a l and chemical changes.
