Department of Agronomy Center for Aquatic and Invasive Plants

Transcription

1 Management of Brazilian peppertree (Schinus terebinthifolius) in Florida mangrove communities. Cody A. Lastinger and Stephen F. Enloe University of Florida Department of Agronomy Center for Aquatic and Invasive Plants

2 Brazilian Pepper Tree

3 Brazilian Peppertree

4 Red Mangrove Rhizophora mangle Black Mangrove Avicennia germinans

5 White Mangrove Laguncularia racemosa Buttonwood Mangrove Conocarpus erectus

6 Current Strategies Basal Bark Treatment (10-20% triclopyr ester)

7 Current Strategies Cut stump treatment (50% Triclopyr amine or % glyphosate)

8 What may be happening: Herbicide flashback 1. Cut stump treatment with triclopyr amine 2. Loss of herbicide from dead or dying roots 3. Herbicide available in soil solution 4. Herbicide absorbed by nearby trees

9 10,000 Islands Everglades National Park

10 Reality: We need new approaches for safer treatment and for remote areas!

11 Objective To develop selective control strategies for Brazilian pepper tree growing in mangrove communities Examine both older and more recently labeled aquatic herbicides Examine herbicide on different Brazilian peppertree life stages Examine the impacts of aquatic herbicides on mangrove species Large plot/field studies Sequential treatments

12 Methods Seedlings 1 to 2 leaf stage Plants 3 weeks old from seed 90 DAT evaluation Shoot height and visual injury Juveniles ~40 cm tall Plants 2 months old 90 DAT evaluation Shoot height and visual injury

13 Methods Well established ~75 cm plants Plants 6 months old 90 Day Evaluation Shoot height and visual Injury Shoot biomass (10cm clip height)

14 Methods Mangroves and Buttonwood 1 gallon pots 180 DAT evaluation Injury (visual assessment)

15 Methods Foliar application 20 gpa Data Analysis Percent reduction in shoot height and injury Multiple comparison using Tukey s protected LSD p=0.05

16 Aquatic Herbicides Evaluated Herbicide Mode of Action Rate kg ai/ha Glyphosate Amino Acid Inhibitors 0.55 Imazamox Amino Acid Inhibitors Bispyribac Amino Acid Inhibitors Penoxsulam Amino Acid Inhibitors Imazapyr Amino Acid Inhibitors 0.18 Carfentrazone PPO Inhibitors Flumioxazin PPO Inhibitors 0.07 triclopyr Auxin Types ,4-D Auxin Types Fluridone Carotenoid Biosynthesis Inhibitor 0.04 Topramezone Carotenoid Biosynthesis Inhibitor Diquat PSI inhibitor 0.73 endothall Not Classified 2.48

17 Brazilian peppertree, 90 DAT

18 Glyphosate Imazamox Imazapyr

19 Brazilian peppertree, 90 DAT

20 Triclopyr 2,4-D

21 Brazilian peppertree, 90 DAT

22 Diquat Flumioxazin on Seedling

23 Mangroves: Run 1, 180 DAT

24 Mangroves: Run 2, 180 DAT

25 Imazapyr on black and red mangrove Run 1 Run 2

26 Mangroves: Run 1, 180 DAT

27 Mangroves: Run 2, 180 DAT

28 Triclopyr on white and red mangrove

29 Mangroves: Run 1, 180 DAT

30 Mangroves: Run 2, 180 DAT

31 Mangrove sensitivity to Diquat White Black

32 Red mangrove sensitivity to Diquat

33 Conclusions to date Brazilian pepper tree Amino acid inhibitors: Imazamox and imazapyr most effective treatments and glyphosate was effective on well established plants Growth regulators: Triclopyr > 2,4-D PPO inhibitors: control decreased as plants became more established, worked well on seedlings Carotenoid biosynthesis inhibitors not effective PSI inhibitor: diquat provided excellent control but effectiveness decreased as plants became more established

34 Conclusions to date Brazilian pepper tree (cont.) triclopyr, imazapyr, and glyphosate demonstrated promise in control of Brazilian pepper tree Imazamox was the only newer herbicide to show useful activity

35 Conclusions to date Mangrove All herbicides that demonstrated efficacy on Brazilian pepper tree, resulted in injury to at least one of the mangrove species. Herbicides that did show great efficacy on Brazilian peppertree, caused injury to some or all of the mangrove species All three species of mangrove and buttonwood demonstrated sensitivity to the aquatic labeled herbicides

36 Injury observed on Mangroves from Herbicides that were effective on well established Brazilian peppertree Red Black White Buttonwood Glyphosate Imazamox Imazapyr Triclopyr

37 Next Steps Examine herbicides that may gain aquatic registration and tank mixes Field experiments Individual plant treatments

38 Acknowledgements FWC Dr. Enloe Students and staff at the CAIP

39 Questions?