Control of Lead Tree, Brazilian Peppertree and Australian Pine

Brent SellersRange Cattle Research and Education Center

• Leucaena leucocephala• Legume family• 20 – 30 ft tall; 4-6 inches diameter

Lead Tree

Lead Tree Distribution

• Leaves • Alternate• Bipinnate• 4 to 12 inches long• 3 to 10 pairs of pinnae• Axes gray-green & finely

hairy• Gland located on axes of leaf

between lowermost pinnae• Leaflets

• Opposite• 10 to 20 pairs• 8-15 mm long x 3 mm wide• Fold upward at night

Lead Tree Leaves

• Tiny• White or pale yellow• Arranged in dense, ball-

like heads ~3/4 in. diameter

• Usually raceme-like at end or side of branches (“terminal”)

Lead Tree Flowers

• Pods oblong• 4 to 6 inches• Flat and thin• Pointed tip• Minutely hairy• Split open at both ends• 10-20 flattened seeds

• Seeds• Oval• Flattened • Pointed

Lead Tree Seed

Lead Tree or Mimosa?

• Seeds & leaf tips = food• Mimosine toxicity

• Coffee substitute• Biofuel crop• Companion crop• Fodder

Lead Tree Utilization (Past)

Lead Tree – Mechanical

• Aminopyralid (Milestone)• 10% v/v (label)• 2.5% v/v (applicator experience)

• Aminopyralid + triclopyr (Capstone)• 100% (undiluted herbicide)

• Triclopyr ester (4 lb ae/gal)• Garlon 4 Ultra & generics (10-25% v/v)• Pathfinder II (100% v/v; undiluted)

Lead Tree – Cut Stump

• Triclopyr ester (4 lb ae)• Garlon 4 Ultra (20-25% v/v)• Pathfinder II (100% v/v;

undiluted)

Lead Tree – Basal Bark

Basally Treat This!

• Aminopyralid(Milestone)

• 7 oz/A (max. label rate)• 14 oz/A spot trt; <50%

of an acre• 0.1% v/v on seedlings

(applicator experience)

• Aminocyclopyrachlor• Talk later

Lead Tree - Foliar

Brazilian Peppertree

• Multi-stemmed trunk• 10 to 40 ft tall• <4 in DBH (3 ft)

• Compound leaves• 2-10 cm long; 1-3.5 cm

wide• 7 (3-15) glabrous

leaflets (toothed)

• Distal flowers• Primarily dioecious

Brazilian Peppertree

• Native to South America• Two introductions in Florida

• Punta Gorda (Type A)• Miami (Type B)

• Hybridization – possible “cold” tolerance

• ~283,000 hectares in Florida• Disturbed & natural areas

• High fecundity• Environmental tolerance

Brazilian Peppertree

• Seedlings• 20% resprout after fire• Flood tolerant, except for extreme changes• 30 to 60% viability; <1% at 5 months

• Flowering• September through November• Male flowers = 1 d; Female flowers = 6 d

• Trees live up to 35 yrs

Brazilian Peppertree

• Control• Foliar

• Triclopyr amine – water soluble• Triclopyr ester – oil soluble

• Basal• Triclopyr ester• Hexazinone (soil app)

• Cut-stump• Triclopyr amine (3 lb ae/gal) 50% v/v• Glyphosate (4 lb ae/gal) 50-100% v/v• Triclopyr ester (4 lb ae/gal) 10-20% v/v; Pathfinder II 100% v/v

Australian-pine (Casuarina spp.)

• Angiosperm• Large trees

• 20-46 m tall• Evergreen

• Single trunk• Leaves=scales• Samaras

Australian-pine

• Native to Australia, South Pacific, Southeast Asia

• 1890s• Windbreaks• R to salt spray

• Grow ~2 m/yr• Hybridization• 1,000s seeds/tree

Australian-pine

• Seeds• Disseminated in air or water currents• Germinate within 14 d in fresh or salt water• Viable up to 2 yrs

• Flowers• Monoecious• Spring and summer; peak April to June

Australian-pine

• Control• Basal bark

• 10-20% triclopyr ester• Cut-stump

• 50% triclopyr amine• 10-20% triclopyr ester

• Frill (larger trees)• 20% triclopyr ester• Addition of 3% imazapyr = more consistent

Aminocyclopyrachlor

• Aminocyclopyrachlor (ACP) new growth regulator herbicide(similar to picloram)

ACP Products

• Method• ACP 2 lb/gal

• Perspective• ACP 39.5%• Chlorsulfuron 15.8%

• Streamline• ACP 39.5%• Metsulfuron 12.6%

• Viewpoint• ACP 22.8%• Metsulfuron 7.3%• Imazapyr 31.6%

BP Cut Stump

• Westin (2011) and Okeechobee (2012), FL• 2011 – oil formulation • 2012 – amine formulation

• Cut trees to 4”; 4-8” diameter• Treated immediately after cutting• Mixed in basal oil• Regrowth monitored 6, 12 and 24 MAT

BP Cut Stump

Experiment 1 (Oil)

Treatment Rate (% v/v)

ACP 0.5

ACP 1.0

ACP 2.0

ACP 4.0

ACP 8.0

Triclopyr-ester 20.0

Untreated -

Experiment 2 (SL)

Treatment Rate (% v/v)

ACP (360 SL) 1.7

ACP (360 SL) 3.3

ACP (360 SL) 6.7

ACP (360 SL) 10

ACP (260 SL) 10

Triclopyr-ester 20

Untreated -

BP Cut Stump I Results

0

20

40

60

80

100

120

ACP0.5%

ACP1.0%

ACP2.0%

ACP4.0%

ACP8.0%

Triclopyr20.0%

Untreated

Perc

ent

12 MAT 24 MAT

BP Cut Stump II Results

0

20

40

60

80

100

120

ACP1.7%

ACP3.3%

ACP6.7%

ACP10.0%

ACP*10.0%

Triclopyr20.0%

Untreated

Perc

ent

12 MAT 24 MAT

BP Foliar

Experiment 1 (2012)

Treatment Rate (oz/A)

Streamline 7.0

9.5

11.4

Viewpoint 13.0

16.0

20.0

Triclopyr-ester 96.0

Untreated

Experiment 2 (2013)

Treatment Rate (oz/A)

Streamline 9.0

11.4

14.0

Viewpoint 16.0

20.0

24.0

Triclopyr-ester 96.0

Untreated

BP Foliar I Results

0

20

40

60

80

100

120

Streamline7.0 oz

Streamline9.5 oz

Streamline11.4 oz

Viewpoint13.0 oz

Viewpoint16.0 oz

Viewpoint20.0 oz

Triclopyr96.0 oz

Perc

ent

90 DAT 12 MAT 24 MAT

BP Foliar II Results

0

20

40

60

80

100

120

Streamline9.0 oz

Streamline11.4 oz

Streamline14.0 oz

Viewpoint16.0 oz

Viewpoint20.0 oz

Viewpoint24.0 oz

Triclopyr96.0 oz

Perc

ent

90 DAT 12 MAT

Australian-pine Foliar

• July, 2013• December, 2013• Hialeah, FL• Single nozzle; 25 GPA• Foliar

Treatment Rate (oz/A)

Streamline 7.5

9.5

11.5

Viewpoint 12.9

16.4

20.0

Triclopyr-ester 96.0

Untreated

Australian-pine Results

0

20

40

60

80

100

120

Streamline9.0 oz

Streamline11.4 oz

Streamline14.0 oz

Viewpoint16.0 oz

Viewpoint20.0 oz

Viewpoint24.0 oz

Triclopyr96.0 oz

Perc

ent

90 DAT 12 MAT

• July, 2015• MacDill AFB• Single nozzle, 25 GPA• Foliar• Trees were previously

cut and stumps treated with glyphosate

Treatment Rate

Method 0.25% v/v

Method 0.375% v/v

Method 0.5% v/v

Method + Arsenal 0.5 + 0.5% v/v

Method + Garlon (3) 0.5 + 0.25 % v/v

Method + Garlon (3) 0.375 + 0.5% v/v

Method + Garlon + Krenite 0.5 + 0.25 + 3% v/v

Streamline 30.3 oz/100 gal

Viewpoint 51 oz/100 gal

Milestone 0.33% v/v

Lead Tree - Foliar

0 10 20 30 40 50 60 70 80 90 100

Method (0.25)

Method (0.375)

Method (0.5)

Meth + Ars (0.5 + 0.5)

Meth + Gar (0.5 + 0.25)

Meth + Gar (0.375 + 0.5

Meth + Gar + Kre (0.5 + 0.25 + 3)

Streamline (30.3)

Viewpoint (51)

Milestone (0.33)

Control (%)

Lead Tree Control – 90 DAT

Lead Tree – Method + Arsenal

• Email: sellersb@ufl.edu• Website: uflweed.com

FYI