Measuring Milkweed Density
All participants must complete the “Milkweed Density Datasheet”
Since the milkweed may not all be above ground at the beginning of the season, you should wait to do the density measurements until the middle of the season. You only need to complete this activity once.
If you can easily count all of the milkweed plants at your site, record the actual number of milkweeds at the site and the size of your site.
If your site has too many milkweed plants to count, you will need to randomly
sample points to obtain plant density data, counting the number of milkweed
plants in several 1 meter squares. To do this, randomly choose a direction
and walk one or more transects, or paths, through the site. Stop every 5-10
paces, and use a meter stick to delineate a square that is 1 meter on each
side. Count all of the milkweed plants within that 1 m2 square. The number
of paces will vary with the size of your site, but must be consistent for
all of your samples. Record the data on the Milkweed Density Data Sheet. Continue
with this method until you have sampled up to 100 squares (the more squares
you sample the more accurate your density estimate will be, but more than
100 is not necessary). The goal is to sample randomly and obtain data that
are representative of the whole site. It is very important not to let the
presence or absence of milkweed influence your choice of samples.
