1. FIA New Growth Accounting System: A State-Partner Perspective Chris Edgar Texas A&M Forest Service March 20, 2014 1

2. What is the issue?  In September 2011 FIA cautioned users not to use data retrieval tools for net growth and removals by diameter class  At this meeting last year it was announced that FIA had implemented a new growth accounting system and that it applied to all attributes that can change between inventories 2

3. What questions are addressed in this talk?  What GRM options are available to users?  How do the options differ among data retrieval tools?  What are some considerations for analysis using the new system? 3

4. What FIA tools are there?  FIDO  EVALIDator  EVALIDator-PC 4

5. Source: FIA Fiscal Year 2012 Business Report 5

6. FIDO Other EVALIDator- PC EVALIDator 6

7. Hurricane Rita 24 Sep 2005 771,000 acres of Texas timber damaged or affected Hurricane Ike 13 Sep 2008 473,000 acres of Texas timber damaged or affected 7

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10. Net growth – total Data Retrieval ToolCubic feet per year FIDO693,255,597 EVALIDator-PC693,255,603 EVALIDator Accounting693,328,343 Previous693,328,343 Current693,328,343 All live on forestland, ETX 2012 10

11. Net growth – total  Estimates from the various retrieval tools match pretty well  New growth accounting system implemented in EVALIDator  Temporal basis selection  Accounting, previous, current 11

12. http://apps.fs.fed.us/Evalidator/evalidator.jsp 12

13. Summarizing by an attribute  Often there is interest in summarizing total net growth by an attribute made up of classes  Attributes commonly used are based on a characteristic of the plot, condition, or tree  Plot – for example county or ecoregion  Condition –for example owner or forest type  Tree – for example species or diameter 13

14. Net growth – oak/hickory group Data Retrieval ToolCubic feet per year FIDO63,087,704 EVALIDator-PC63,087,704 EVALIDator Accounting31,825,275 Previous66,450,351 Current63,091,182 All live on forestland, oak/hickory forest type group, ETX 2012 14

15. Net growth – oak/hickory group  FIDO and EVALIDator-PC estimates match  New growth system has not been implemented in these tools  Estimate summarized based on the attribute’s current inventory value  EVALIDator-PC has some limited options for summarizing on previous inventory value  Diameter class and stand-size class 15

16. Net growth – oak/hickory group  EVALIDator estimates vary depending on the temporal basis selected  An expected outcome because the attribute, forest type group, can change between first measurement and second measurement 16

17. How much change occurred?  In considering summarizing by an attribute it can be helpful to know whether the attribute changes and how much  For condition-level attributes, run an area change retrieval in EVALIDator  Row = Attribute – previous temporal basis  Column = Attribute – current temporal basis 17

18. Current Previous http://apps.fs.fed.us/Evalidator/evalidator.jsp 18

19. Previous temporal basis  Growth on conditions typed oak/hickory at the previous inventory (time 1)  ~ 3.0 million acres total  71 percent oak/hickory group at time 2  23 percent another forest type group at time 2  6 percent classified “other” at time 2 (nonforest)  Net growth of 66.5 million cubic feet per year 19

20. Current temporal basis  Growth on conditions typed oak/hickory at the current inventory (time 2)  ~ 2.8 million acres total  76 percent oak/hickory group at time 1  19 percent another forest type group at time 1  5 percent classified “other” at time 1 (nonforest)  Net growth of 63.0 million cubic feet per year 20

21. 21 http://apps.fs.fed.us/Evalidator/evalidator.jsp Current Previous

22. Temporal basis considerations  Interested in what happened to oak/hickory forests  This suggests previous temporal basis  Interested in what the outlook is for oak/hickory forests  This suggests current temporal basis  Both estimates are valid 22

23. Accounting estimate  Accounting estimate provides the best overall match to net growth calculated from inventory and removals Annual net change = Annual net growth – Annual removals Rearrange to get Annual net growth = Annual net change + Annual removals 23

24. An approximate value  Inventory in oak/hickory  2007 evaluation = 3,237.6 million cu ft  2012 evaluation = 2,983.8 million cu ft  Annual net change = -50.8 million cu ft  Removals in oak/hickory (previous)  Annual removals = 76.8 million cu ft  Annual net growth = 26.0 million cu ft 24

25. Net growth – oak/hickory group Data Retrieval ToolCubic feet per year FIDO63,087,704 EVALIDator-PC63,087,704 EVALIDator Accounting31,825,275 Previous66,450,351 Current63,091,182 All live on forestland, oak/hickory forest type group, ETX 2012 Nearest to the approximate value of 26.0 million 25

26. Communicating with clients  No difference on grand totals  Differences arise when summarizing by attributes  Small differences if attribute changes infrequently  Large differences if attribute changes frequently  Different resources are estimated  All estimates are valid  Understand what resource is estimated and whether that is what is sought 26

27. Thank you. Questions? Chris Edgar Texas A&M Forest Service 200 Technology Way, Suite 1281 College Station, TX 77845 (979) 458-6630 cedgar@tfs.tamu.edu 27