Lab report: turn in report with title, objectives, methods, results including tables and graphs, discussion, and possibilities for improvements. Hint: just add these text items to your spreadsheet and print it out.

Taking lab data and determining degree-day requirements: spreadsheet exercise (all methods presented during introduction)  

Methods: use x-intercept and lowest CV methods to determine developmental (degree-day) requirements and compare results:

Lab data: orange tortrix egg stage

 

Temp oC	Dev time in days
12	33.5
16	15.6
20	10.6
24	7.5
28	7.2
32	no hatch

 

Field data: orange tortrix egg stage 2005
Methods: 1) Use DD calculator at http://pnwpest.org/cgi-bin/ddmodel.pl to calculate any missing values in the table below. Be sure to check "Deg. Celsius", "Double Triangulation", and the year "2005" in addition to the proper thresholds and starting dates. Make end dates anytime after the last date of the interval.
2) Use lowest CV method; compare to constant temperature results:

Avg. Deg-days (double triangle method, DD4 means deg-days at a lower threshold of 4 degrees Celsius)

Date oviposition	Date Hatch	Days	DD4	DD5	DD6	DD7
5/27	6/14	18.9	187	169	151	133
6/28	7/11	13.2	162	149	136	123
7/17	7/28	11.7	164	153	142	___
9/14	9/28	14.3	181	168	___	___

1) Compare and contrast results. What did you find?

2) What are the advantages/disadvantages of each method?

3) Which method would you rely on most for an IPM decision support model? Why?

4) Using degree-day model for orange tortrix - mild winter (http://pnwpest.org/cgi-bin/ddmodel.pl?otm), run the model for default settings.

   a) When is first egg hatch predicted in 2006?

     b) How does date of first hatch compare to last year?

     c) How many DDs are there in the model between egg-laying and egg-hatch? How does this compare to your analysis? (Remember to convert scales)