1. Fertilization

2. Objectives What factors affect fertilization decisions How to find information needed How to calculate application costs

3. Silvicultural Tools Plant Kill Ameliorate site

4. Ameliorate Site Irrigate Drain Subsoil Fertilize

5. What? How much? When? How?

6. The Details Fertilizer guide: http://www.for.gov.bc.ca/tasb/legsregs/fpc/fpcg uide/fert/ferttoc.htm Written in 1995 (Forest Code)

7. What Law of the minimum Law of compensation

8. Law of the Minimum Growth is limited by whatever factor is most need

9. Nitrogen Potential Growth Actual Growth

10. Law of Compensation The addition of one factor can increase the efficiency that a tree uses another factor

11. Law of Compensation With P Amount of N Growth Rate

12. How Much? Rule of efficacy What is needed Cost Returns

13. Rule of Efficacy Diminishing returns Growth Amount of “X”

14. Nutrient Cycling Availability CEC Weathering Mineralization C:N Nutrient capital Translocation

15. Fertilization Affects trees Does not affect site

16. Ratings Amount (percentage) of elemental Nitrogen (N); Phosphorous pentoxide (P 2 O 5 ); and Potassium oxide (K 2 O) Ex. 12-20-10 = 12%N; 20% (P 2 O 5 ); 10%(K 2 O)

17. Ratings 100kg would then have 12kg N; 20kg (P 2 O 5 ); 10kg (K 2 O) Atomic weights: N=14.01K=39.10 P=30.98O=16.0

18. Ratings (P 2 O 5 ) = (2 * 30.98) (2 * 30.98) + (5 * 16.0) or 43.65% P So 43.65% of 20kg = 8.7kg P

19. Analysis Soil Foliar

20. Effect Affects plants Does not affect site (response is shortlived) Affects stand dynamics

21. Target Species Non-trees can have more rapid uptake Can be detrimental (more competition)

22. When? Get above competition during establishment Increase diameter just before thinning or harvest Shorten rotation

23. How? “ Teabags” Sidecast Helicopter

25. Cost Application plus fertilizer How much will reach trees? Most effective on medium site indicies