Application Results

2023:

Billerica:

• 92.22% average reduction at monitored dip stations, 25% increase at the control site 

Boxborough:

• 78.87% reduction at monitored dip stations, 67.76% decrease at the control sites 

Chelmsford:

• 99.33% reduction at monitored dip stations, 11.07% decrease at the control sites

Overall larval reduction: 92.88%

2023 Individual Site Monitoring Results:

Some observations: in general we don’t see a reduction of larvae in our control (untreated) areas, but we did receive some rain between the time we dipped for larvae and the application. This caused the wetland sites to increase and some of the larvae may have moved away from the dip station areas. The site in Boxborough with the notation “No BTI present” means we did not see the Bti at our monitoring stations, however when we looked elsewhere in that wetland we did see Bti and no larvae in those areas. The areas around our monitoring stations that were missed were treated by hand.  

As you can see from the raw numbers in the treated areas, control was excellent. Some of the sites had the largest number of larvae pre-dip than we have seen in many years.

A full report will be uploaded to our website at this link: https://www.cmmcp.org/research-efficacy/pages/2023-research-projects