| Purple loosestrife is an invasive weed which
has recently taken hold in the Millbrook Marsh near State College, PA.
A GPS was used to record reference point locations of along two survey
transects for monitoring the weed population (green
dots), and release points of a potential biological control agent
(a weevil, Hylobius transversovittatus). The weevil is introduced
to an area by inserting a individual eggs into a clipped stem of a weed
plant. On 25 August 2000 a large number of weevil eggs were
placed in plants of the Millbrook Marsh (yellow Xs
on the map below). The GPS can be a powerful tool used in
monitoring the establishment and spread of a population. Several additional
features have been marked on the digital photo below: two wells,
two points of stream confluence, and a the location of a footbridge for
crossing one of the streams.
Plans for the future involve educational field trips for school classes
to learn about these wetlands and participate in the monitoring of both
the weed population's spread (or decline?), as well as development of the
beetle's population. |
