Database Reference
In-Depth Information
Table 11.1
Start date
End date
Winter
355
80
Spring
81
171
Summer
172
263
Fall
264
354
Larva 1
Hourly Temp
Rate 1
Pesticide
Rate 2\3
Reproductive Adults
Egg Laying
Day Accumulation
Larva 1 Death
Larva 3 Death
Day Accumulation
Hourly Temp
Eggs to 1st
Egg Death
Second to Third
Third to Adult
Larva 2
First to Second
Larva 1
Eggs
Larva 3
Adult
Larva 2 Death
Rate 2\3
Hourly Temp
Hourly Temp
Adult Death
Maturation
Reproductive Adults
Fig. 11.18
and the model is currently evaluated based on an initial overwintering population
of 10,000 first instar larvae. Death rates for each life stage have been constructed to
simulate field population dynamics.
To model the effects of
Adelges piceae
on the Fraser fir population, we con-
structed a counter (Figure 11.19). The Sucker Adder counts the Total Suckers at
each DT, and sums the change. Since each Fraser fir tree can host 50,000
A. piceae
before it reaches death, the Sucker Adder was set to empty at this value. Thus, for
every value of 50,000
A. piceae
, a value of one was sent to the Sum of Damage stock,
and in turn, one tree was infected.
The uninfected
Fraser fir
population began at 19 (1 infected tree arrived at our
site), and this population quickly decreased as the uncontrolled
A. piceae
population
grew and spread to new hosts (Figure 11.20).
