1. The document discusses research into developing a pine bark-based soilless substrate that improves water and nutrient retention in containerized plant production. 2. The researchers tested adding various mineral aggregates and clays as amendments to the substrate at different rates and particle sizes. 3. Their results showed that a substrate with 11% clay amendment (by volume) with particles sizes of 0.25-0.85 mm increased water and nutrient use efficiency, allowing for a 26-32% reduction in water application while maintaining plant growth.

1. Amendments that improve water retention Jim Owen, Jr., Stuart Warren, Ted Bilderback, Dean Hesterberg, Alison Prehn, and Joseph Albano NC STATE UNIVERSITY

2. The Team

4. Approach NUTRIENTS ENVIRONMENT IRRIGATION SUBSTRATE Container

5. Approach NUTRIENTS ENVIRONMENT IRRIGATION SUBSTRATE Container

8. Amendment Raw Clay Selection & Mining Primary Crusher Secondary Crusher Dryer (RVM) Mill Screen Rotary Kiln (LVM) Oil-Dri Corporation of America Bag or Bulk ≤ 800 °C ≈ 120°C

11. Water and nutrient (N & P) budgets

14. Clay Rate

15. Clay Rate Physical Properties Normal Range

16. Clay Rate Physical Properties Normal Range

17. Clay Rate Max. = 11% Y = 0.6x 2 + 13.3x + 247.0 R 2 = 0.76

19. Reduced Water Application

20. Reduced Water Application How Low Can You Go!

22. Reduced Water Application

23. Reduced Water Application 26 L

24. Reduced Water Application 90,000 gallons of water saved per growing acre while maintaining growth

25. Reduced Water Application 16 L

26. Reduced Water Application 55,000 gallons less leachate or runoff per growing acre

27. Water Buffering Capacity

29. Water Buffering Capacity

30. Water Buffering Capacity

31. Water Buffering Capacity 3.4 mL min -1 2.7 mL min -1

32. Water Buffering Capacity 334 mL

33. Water Buffering Capacity Physical Properties: 4% increase in available water which equates into 500 ml

35. Water Buffering Capacity B P ≤ 0.05 A B A B 123 g 82 g

36. Water Buffering Capacity B P ≤ 0.05 B A B A 190 mL 90 mL

37. Financial Support FNRI

38. Columbia River Gorge, OR