The local agricultural official gave the fruit growers of the District 10 Farmers' Cooperative a new pesticide that they applied for a period of three years to their pear orchards in place of the pesticide they had formerly applied  During those three years, the proportion of pears lost to insects was significantly less than it had been during the previous three-year period
On the basis of these results, the official concluded that the new pesticide was more effective than the old pesticide, at least in the short term, in limiting the loss of certain fruit to insects
The amount of fruit that an orchard can potentially produce depends in part on how many mature trees it contains, and the number of mature pear trees in District 10 has declined steadily over the past eight years.