The rate suggested 1n the thinning circular is based on 

 Sevin* W. This means a grower will use 1/2 pound per 100 gallons 

 of Sevin* SOW (which is equivalent to 1/4 pound of actual carbaryl) 



*************** 



COMPARATIVE RESPONSES OF PEACH TREES TO CHEMICAL 

 WEED CONTROL, HAY MULCH, FREQUENT MOWING AND CULTIVATION 



W.J. Lord and Edward Vlach 

 University of Massachusetts 



n was recently completed in which 

 aquat-pl us-simazi ne , frequent mowing, 

 tments on growth, yield and nutri- 

 es were compared. The data obtained 



1. The growth and yield of trees which received annually 2 

 applications of paraquat or 1 application of a paraquat- 

 pi us-simazi ne mixture were comparable to the trees main- 

 tained under cultivation or mulched annually with a 40- 

 Ib bale of hay. 



2. Annual grassy and broadleaf weed were not as readily con- 

 trolled by the residual simazine in the soil from the annu- 

 al applications of the paraquat-pl us-simazi ne mixture in 

 early May as by 2 applications of paraquat annually in 

 early May and-mi-d-July . 



3. There is concern about complete elimination of weed cover 

 under fruit trees with herbicides. With no snow cover, 



a soil free of weeds might expose fruit trees to a deep 

 soil freeze and root injury. Complete control of peren- 

 nial grasses and broadleaf weeds was not obtained. In ad- 

 dition, annual grassy and broadleaf weeds generally in- 

 vaded the herbicide-treated areas and by late summer the 

 weed population frequently was as dense as under cultivated 

 trees . 



4. An annual application of a 40-lb bale of hay resulted in 

 peach tree performance comparable to cultivation. Hay 

 mulch increased leaf potassium (K) in comparison to the 

 other treatments and high leaf K was associated with de- 

 pressed magnesium levels. 



5. Trees that were mowed 4 or 5 times during the growing sea- 

 son generally were lower in nitrogen, made less growth 

 and produced less fruit than the other treatments. These 

 trees were probably more sensitive to periods of moisture 

 stress, as indicated by trunk circumference increase. 



