Assessment of Macrophyte and Sediment Concerns

1. Assessment of Macrophyte and Sediment Concerns Jess Hesley, Tyler Jack, Christina Leid University of Idaho Limnology Service Learning Project December 7th, 2011

2. Outline • Background • Methods • Sampling • Analysis • Results • Recommendations

3. The OX Ranch near Council, ID Photo Credit: Frank Wilhelm

4. Sampling Methods: Macrophytes • Site Selection • Collection

5. Sampling Methods: Sediment • Site Selection • Collection

6. Analysis Methods: Macrophytes • Preparation • Drying

7. Analysis Methods: Sediment • Preparation • Drying

8. Results • Macrophytes • Species ID • Biomass • Sediment • Water Content • Deposition

9. Vegetative Culprits • CeratophyllumdemersumCoontail • Ceratophyllumechinatum • Spiny Hornwort • Myriophyllum spp. • Milfoil

10. Biomass Determination

11. Water Contents

12. Sediment Deposition Pond Wide Total: ~787 m3 Annual: ~44 m3 By Polygon A: 107m3 B: 462 m3 C: 215 m3 Photo Credit: Frank Wilhelm

13. Deposition by Polygon

14. Review of Concerns • Macrophytes • Biomass • Invasive nature • Sediment • Deposition • Altering pond structure

15. Recommendations

16. Determining factors for - Dredging • Positive Impacts: • Reduction of suitable habitat for rooted macrophytes. • Removal of nutrients stored in the plant structures. • Swimming and fishing will be greatly improved for 2013 • summer season. • Negative Impacts: • Fragmentation and threat of re-colonization.

17. Determining factors for – Drawdown, Benthic Barriers, and Hand-pulling Positive Impacts: • Drawdown mitigates fragmentation re-colonization. • Placement of benthic barriers proven to reduce growth of macrophytes. Negative Impacts: • May require fish capture and transport to avoid fish kill. • Requires restocking of fish.

18. Determining factors against – Herbicides and Shading Herbicides • Do not address the cause or source of the problem. • Short lived and may require re-application. • The long term impact of herbicides on humans, non-targeted plants, and animals is relatively unknown. Shading • While non-toxic it will impact aesthetics and all species within the pond.

19. Dark blue – area dredged to a depth of 3 m. • White – area recommended for the placement of benthic barriers. • Yellow – area of intensive use recommended for potential hand-pulling treatment. • Red – Installation of docks for fishing accessibility.

20. Other Considerations • Impacts of nutrient addition from adjacent fields of agricultural use. • Installation of additional docks to provide improved fishing access.

21. Estimated Expenses

22. Timeline

23. Conclusion Sediment accumulation is the ‘root’ of the macrophyte growth problem. Mitigate macrophyte growth through: • Drawdown • Dredging • Benthic Barriers • Hand-pulling Photo credit: www.crappielake.com

24. References • Center for Aquatic and Invasive Plants. (2011). University of Florida IFAS Extension. Retrieved from http://plants.ifas.ufl.edu/ • Fewless, G. Invasive Plants of Wisconson. (2011). Retrieved from http://www.uwgb.edu/biodiversity/herbarium/invasive_species/myrspi01.htm • Krebs, C. J. (1998). Ecological methodology. (2nd ed.). Menlo Park,CA:Benjamin/Cummings. • Maine's interactive field guide to aquatic invaders and their native look alikes. (2009). Retrieved from http://mainvolunteerlakemonitors.org/ mciap/ herbarium/Hornworts.php • Susan, B. (1998). Through the looking glass: A field guide to aquatic plants. Madison, WI: University of Wisconson Press. • TroutLodge (2011). Troutlodge price list. Received via personal contact with TroutLodge. www.troutlodge.com

25. Cold Water Pond Stocking Recommendations Guide illustrating stocking recommendations that have been successfully applied in the United States. Other combinations and rates may be used, depending upon the owner’s objectives and site suitability.

26. Organic Content