1. Daniel C. Bowman NCSU

2. What is a Riparian Buffer? Riparian refers to the land and/or ecosystem immediately adjacent to a river, stream or lake. Buffer refers to the biological and physical characteristics of the system which reduce the movement of unwanted materials from the land and into the waterway. Nitrogen and Phosphorus are of major concern.

3. Why Is Nitrogen Harmful? Nitrogen Enters Water Algae Grow Rapidly Algae Use Oxygen for Respiration Oxygen Levels Drop

4. The Neuse River Rules Designed to reduce N in the river by 30% Designed to distribute responsibility among waste water treatment facilities, developers, farmers, and other fertilizer applicators (you) Substantially based on scientific principles, but also chock full of politics

5. Who Are “Other Fertilizer Applicators”? Anyone who applies fertilizer to 50 or more acres of, among other areas, turfgrass: including golf courses, recreational areas, lawns, etc.

6. You Have Two Choices: Complete a training course on nutrient management. You must sign up for the course during year one and complete the course within 5 years Develop a written nutrient management plan for all fertilized areas. You may use NCSU’s fertilizer guidelines for turfgrass management.

7. Rain and Irrigation Moves Through a Porous Soil Soil Cross-Section

8. Heavy Precipitation May Cause Runoff, Intermittent Flow

9. Water Moves Through Porous Soil at Top of Profile Aquatard

10. Aquatard Directs Subsurface Flow into a Stream Aquatard

11. Nitrate Moves with the Water Aquatard NO 3

12. Perched Water Table Continuous with Stream Aquatard

13. Compacted Layer Under Turf Also Direct Water to Stream

14. What Defines a Stream? This has been a sticky issue. When is a ditch a stream, and when is it just a ditch? Size, width? Period of flow? Amount of flow? Presence of aquatic organisms? Characteristics of stream bed?

15. Neuse Shoreline is Relatively Small Compared to the Shoreline of Tributaries Neuse River

16. Buffers Remove Nitrate From Flowing Groundwater Nitrate Concentration Landscape Position Uphill BufferStream

17. Subsurface Flow Zone 2 20 feet Zone 1, 30 feet 20 feet limited harvest/10 ft undisturbed

18. Why Two Zones? Zone One functions to remove NO 3 through denitrification and also to reduce bank erosion. This can be crucial where livestock are present. Zone Two functions to reduce surface runoff, trap sediments, and increase infiltration. This zone is likely to cause the most problem for turfgrass managers because it is vague and has been poorly conceived from a scientific or practical viewpoint*. * my opinion

19. Zone 2 20 feet Zone 1, 30 feet 20 feet limited harvest/10 ft undisturbed Subsurface Flow Nitrate Profile Through Buffer

20. Zone 2 20 feet Zone 1, 30 feet 20 feet limited harvest/10 ft undisturbed Subsurface Flow Rate of Runoff Through Buffer

21. How Do Buffers Reduce Nitrate? Contrary to popular opinion, buffers do not absorb large amounts of nitrate Buffers do promote denitrification, which converts nitrate-N to gaseous forms of N which are lost to the atmosphere

22. Respiration vs. Denitrification Electrons need to go somewhere, to be accepted NO 3 - NO 2 - NO N 2 O N 2 e-e- e-e- O 2 H 2 O Normal respiration requires oxygen Denitrification, an alternative when there is no oxygen

23. Requirements for Denitrification Waterlogged conditions Presence of nitrate Presence of organic matter Presence of specific denitrifying bacteria NO 3 - NO 2 - NO N 2 O N 2

24. Requirements for Denitrification Waterlogged conditions –the perched water table provides this Presence of nitrate –leaching from ag fertilizer (and natural sources) Presence of organic matter –deep root systems secrete OM, also die Presence of specific denitrifying bacteria –always present in most soils

25. Problems with Zone Two No plant material list. What qualifies? No fertilizers/pesticides allowed. This will lead to stand thinning, increased weediness, increased runoff, increased erosion, and increased non- compliance. Objections to this have been communicated by the scientific community, but it is unclear that anyone was listening.

26. Which Plants for Zone One? Native woody vegetation. Deep-rooted. Selective harvest? Selected ornamentals. Deep-rooted woody and herbaceous. NCSU Cooperative Extension may be asked for a list of appropriate plant materials.