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By first determining when and at what quantities pests are present, we can 

 time accurately chemical applications to coincide with damaging pest levels. 

 The intent of IPM rarely is the elimination of pesticides. It usually means 

 minimizing chemical use. The benefits of IPM are not only realized at the time 

 of implementation of the program but are also long-term. Ecological, 

 economic, and sociological concerns are paramount when considering development 

 or implementation of an IPM program. 



Integrated pest management gives maximum consideration to the fine 

 ecological balances among all of the components of an agricultural system. 

 Attention is paid to the life cycles of the pests and the extent of their 

 interaction with the host plant. Host plant phenology, or the developmental 

 stages of plants, are investigated extensively together with the pest and 

 natural enemy life cycles. 



Tn an IPM program, the decision whether or not to implement control 

 measures is based upon economic threshold levels. These levels are the lowest 

 pest population densities that will result in economic damage. Thus, it is 

 important to monitor pest populations throughout the growing season so that 

 control decisions can be made to prevent economic losses. It is also important 

 that the cost of control does not exceed the marketable value of the commodity. 

 Because pests and their population levels change during the course of the 

 growing season, threshold levels may be different for different plant parts and 

 at different times during the season. 



Threshold levels are based on two types of pests: 1)direct pests - those 

 which affect the marketable part of the plant, for example, the berries of a 

 cranberry plant, and 2)indirect pests - those which attack the non-marketable 

 parts, for example, leaves, stem, and roots. Because the fruit are the parts 

 of cranberries which are marketed, the threshold levels for direct pests are 

 extremely low, especially if the berries are sold for fresh-market purposes. 

 Keep in mind, that the importance of attack on the different plant parts varies 

 from crop to crop. In the case of ornamentals where the entire plant is used 

 for aesthetic purposes, direct and indirect pests may be of equal importance 

 from an economic standpoint and the need to control. 



The Cranberry IPM program (1983 to 1985) successfully sparked grower 

 interest in the concepts if IPM and demonstrated significant monetary savings. 

 As growers become increasingly aware of the benefits of IPM, they tend to 

 utilize information distributed via this program, regardless of whether of not 

 they are formal participants in the program. 



1986 and 1987 Scouting Program 



Fifteen growers were involved in the cranberry IPM program in 1986. This 

 figure more than doubled in 1987, with 33 participants. The total number of 

 acres in the 1986 program was 208, increasing to 450 in 1987. The largest 

 acreage contracted from an individual grower was 50 and the smallest was 0.58. 

 All growers were visited in early May by the cranberry IPM coordinator to 

 discuss specifics and procedures for the program. Also at this time, 

 recommendations were made for spring weed control. 



