- 10 - 



that reliable growth and yield data could not be obtained in 1972 

 and 1973 and the experiment continued for another 2 or 3 years. 



DISCUSSION 



Younger fruit trees are less tolerant of herbicides than 

 older trees. The tolerance difference probably is due to the lim- 

 ited root system and "depth protection" of newly-set trees. The 

 results from the present experiment show that hay mulch can be of 

 value for reducing the risk of injury to young trees from pre-emer- 

 gence herbicides (Table 1). Hay mulch decomposes rapidly, however, 

 and additional applications seem necessary to sustain this benefi- 

 cial effect. 



Better weed control in 1972 and 1973, resulting from 12 lbs 

 of dichlobenil applied on the mulch residue rather than on bare 

 soil (Table 2), shows another possible benefit of mulch. Dichlo- 

 benil content was higher in the mulch (7 ppm as compared to 0.5 ppm 

 in the top 0.6 inches of the unmulched soil) and was probably re- 

 sponsible for killing many germinating annual weeds. 



All pesticides listed in this publication are registered and cleared 

 for suggested uses according to Federal registrations and State Laws 

 and regulations in effect on the date of this publication. 



When trade names are used for identification, no product endorsement 

 is implied, nor is discrimination intended against similar materials. 



NOTICE: THE USER OF THIS INFORMATION ASSUMES ALL RISKS FOR PERSONAL 

 INJURY OR PROPERTY DAMAGE. 



WARNING: PESTICIDES ARE POISONOUS. READ AND FOLLOW ALL DIRECTIONS 

 AND SAFETY PRECAUTIONS ON LABELS. HANDLE CAREFULLY AND STORE IN 

 ORIGINAL LABELED CONTAINERS OUT OF REACH OF CHILDREN, PETS AND LIVE- 

 STOCK. DISPOSE OF EMPTY CONTAINERS RIGHT AWAY, IN A SAFE MANNER 

 AND PLACE. DO NOT CONTAMINATE FORAGE, STREAMS AND PONDS. 



I 



