Natural Areas Weed ManagementNatural Areas Weed ManagementCertification TrainingCertification Training

IFAS Short Course 2010IFAS Short Course 2010

Ken Langeland and Jeff HutchinsonKen Langeland and Jeff HutchinsonUF/IFAS Agronomy DepartmentUF/IFAS Agronomy DepartmentCenter for Aquatic and Invasive PlantsCenter for Aquatic and Invasive Plants

Natural AreasCertification

Core Training

•Study Questions for the Certified Pesticide Applicator Examination: Natural Areas Weed Managementhttp://prohort.ifas.ufl.edu/pubs/AG24000.pdf

•Garlon 4 Labelhttp://www.cdms.net/ldat/ld0B0010.pdf

THESE ARE INCLUDED IN THE SHORTCOURSE PROGRAM

Over half of Florida’s land area is in

agriculture or urban land uses and natural

habitats are continually being lost.

Natural areas are protected in > nine

million acres of conservation lands

in Florida.

Invasive Plant SpeciesNonnative (exotic) species that form self-sustaining expanding, populations within natural plant communities.

Brazilian pepper

NOTE: 1,180 of 3,834 plant species in

Florida are nonnative

(31%)

Weeds vs. Invasive Plants ?

Invasive Plant or Weed•Invasive Plant:

Spreads beyond intended area and invades natural areas

Displaces native vegetative and disrupts natural processes

•Weed:

A plant growing where is not wanted (yards, gold courses, etc.)

Does not disrupt natural processes

Why the Concern?• Competition with native

plants– Water– Nutrients– Space

• Alter hydrology

• Alter fire ecology

• Hybridize with native species

What Plants Are InvasiveProhibited – Legislative Authority

USDA - Federal Noxious Weed ListFL DACS - Florida Noxious Weed ListFL DEP - Prohibited Aquatic Plant ListLocal Ordinances

No statutory authorityFLEPPC List of Invasive Species

FLEPPC/FNGA agreement

Florida Exotic Pest Plant CouncilList of Invasive Plants

Category I - Invasive exotics that are altering native plant communities by displacing native species, changing community structures or ecological functions, or hybridizing with natives. This definition does not rely on the economic severity or geographic range of the problem, but on the documented ecological damage caused.

Ex. Melaleuca, Brazilian pepper, Australian pine, OWCF, shoebutton ardisia and others.

Florida Exotic Pest Plant CouncilList of Invasive Plants

Category II - Invasive exotics that have increased in abundance or frequency but have not yet altered Florida plant communities to the extent shown by Category I species. These species may become ranked Category I, if ecological damage is demonstrated.

Ex. Guinea grass, castor bean, queen palm, and wedelia and others.

Questions Regarding the ID of a Plant -Contact any major herbarium at a Florida University (UF, USF, UM, FSU)

Questions Regarding Listed Species -Florida Natural Areas Inventory (FNAI) maintains a list of endangered plants and animals for each county in Florida.

Questions Regarding a Specific Plant –DEP/FWC Regional Biologists or County Agricultural Extension Agent

Land managers, natural resource specialists, invasive

plant technicians, andbiologists should become

familiar with the non-native plant species in this book.

Know: characteristics of some of the most invasive plants

Australian PineBrazilian Pepper

MelaleucaOld World Climbing FernJapanese Climbing Fern

Chinese Tallow

Ex. leaves, fruits, growth habit, bark, etc.

Brazilian Pepper

Alternate Leaves

Odd-PinnateCompound

Toothed Margins

Japanese Climbing FernTwice Compound (3-pinnate)

Old World Climbing FernOnce Compound (2-pinnate)

Chinese Tallow“simple leaves, milky sap”

Australian Pine“pine like needles”

Melaleuca“simple leaves”

“paper-like bark”“parallel venation”

Integrated Pest Management (IPM)• The coordinated use of multifaceted pest and environmental

information with available pest control methods to prevent unacceptable levels of pest damage by the most economical means and with the least possible hazard to people, property, and the environment.

• What IPM is not:– Use of “least toxic pesticides”– Minimum use of synthetic pesticides– Maximum use of biological controls– Alternation of control methods

Five Methods to Control Invasive Plants

Manual

Mechanical

Cultural

Biological

Herbicides

Managing Invasive Plants (5 methods)

Mechanical Manual

Biological

Cultural

Biological controlExamples:Melaleuca - snout beetle, psyllid

Herbicides

Herbicides Used in Natural Areas• Triclopyr amine

– Garlon 3A

• Triclopyr ester– Garlon 4, Pathfinder II

• Glyphosate– Terrestrial: Roundup Pro, Glyphos, Glypro Plus– Aquatic: Rodeo, Aquamaster, Aquaneat, Eagre,

Aquapro, Glypro

Herbicides Used in Natural Areas• Imazapyr

– Arsenal, Stalker

• 2,4-D– Riverdale products, Amine 400 2,4-D Weed

Killer, Weed Rhap A-4D, Weedar 64

• Hexazinone– Velpar L, Velpar ULW

• Metsulfuron methyl– Escort XP

Herbicide Characteristics• Solubility

• Absorption and Translocation

• Persistence– Mobility in soil– Breakdown

• Toxicity

• Mode of Action

Herbicide Solubility

• Water soluble–Polar (electrical charge)

•Salts of acids (e.g. amines)

• Oil Soluble–Nonpolar

•Esters

Herbicide Solubility

• Amine – readily dissolve in water

• Ester – do not mix with water- dissolve in oil

NCl

ClCl

O CH2 CO

O +NHCH2

CH2CH2

CH3CH3

CH3

Triclopyr amine(Garlon 3A)

Polar (charged)- mixes with H2O

NCl

ClCl

O CH2 CO

O CH2 CH2 O CH2 CH2 CH2 CH3

Triclopyr ester (Garlon 4)

Non-polar(no charge)- does not mixwith H2O

Herbicide Solubility• Water soluble

(Polar - amine)

– Glyphosate

– Triclopyr amine

– 2,4-D amine

– Imazapyr

– Hexazinone

– Metsulfuron

• Oil Soluble(Non-polar - ester)

– Triclopyr ester

– 2,4-D ester

Emulsifiable Concentrates (EC)

• Oil soluble products with emulsifiers

• Form emulsions in water

• Examples:– Garlon 4 (triclopyr ester)– Stalker (imazapyr)

“can be mixed in oil or water”

←Garlon 3A

←Oil

Oil

Water

Water

Oil

Oil

OilOil

Oil

OilOil

Oil

Oil

OilOil

Water

Add Emulsifier oil and water mix

No Emulsifier

the polar part of the emulsifier molecule has an affinity with waterand the non-polar part (fatty chain) tends to be attracted to the fatty phase

Herbicide Formulations

• S or WS = Water-soluble

• OS = Oil-soluble

• W or WP = Wettable powder

• DF = Dry-flowable

• E or EC = Emusifiable concentrate

• Others: granules, pellets

Absorption: Movement of a substance (herbicide) into the plant

Adsorption: Retention of a substance on a surface such as soil particle or plant surface

Translocation: Movement of a substance within a plant

Diffusion: Herbicide moves from an area of high concentration to low concentration

Active Transport: Energy requiring; herbicide movement up a gradient from low concentration to high concentration

Lipidbilayer

Concentrationgradient

EnergyDiffusion Channeltransport

Carriermediated Active

transport

Molecules

Passivetransport

No energyrequired

Routes of Herbicide Absorption• Leaves

– Foliar application

• Stems– Basal bark application– Cut stump application

• Roots– Soil application

Foliar Absorption – move downward in the phloem

• Epidermis

– Hairs• Surface tension

– Cuticle (diffusion)• Waxy

– Cell Wall(diffusion)

– Plasma membrane(active uptake)

Know outer layer (epidermis) and its 3 components

Leaf Cross-section

Root Absorption – move upward in the xylem

• Availability– Adsorption

• Humus• Clay

• Root Hair (no cuticle)(Diffusion)

• Move upward in xylem

• Cell wall(Diffusion)

• Plasma membrane(Active transport)

Stem Absorption - move upward in the xylem and/or move downward in the phloem

• Herbaceous–Epidermis

• Cuticle• Cells Wall• Plasma membrane

• Woody–Bark

• Corky• Waxy

Herbicide Translocation - determines ultimate fate of herbicide in plants

• Deactivation– Adsorbed, hydrolyzed, precipitated

• Vascular tissue movement– Xylem

• Non-living - wood• Upward with transpiration stream

– Phloem• Living• Downward with photosynthate

BREAKDOWN AND PERSISTANCE

Moderate30 daysMicrobialHydrolysis

Triclopyr

Moderate30 daysMicrobialMetsulfuron

Moderate25-142 daysMicrobialImazapyr

Moderate120 daysMicrobialImazapic

High(leaching to non-

target area)

90 daysMicrobialPhotolysis

Hexazinone

Bound (none)47 daysMicrobialGlyphosate

Low10 daysMicrobial2,4-D

MobilityHalf-lifeBreakdown

Breakdown of Herbicides• Photolysis – energy (heat) absorbed by

light causes the chemical bonds of molecules to break.

• Hydrolysis – chemical bonds are broken when herbicide reacts with water.

• Microbial – metabolization (degradation) of herbicides by soil microbes.

(Note: herbicide loss also occurs by leaching and adsorption)

Absorption, Translocation And Mode of Action

Organo-auxinPhloemFoliage, rootsTriclopyr

Protien synth.Xylem, phloemFoliage, rootsMetsulfuron

Protein synth.Xylem, phloemFoliage, rootsImazapyr

Protein synth.Xylem, phloemFoliage, roots Imazapic

PhotosynthesisXylemRootsHexazinone

Protein synth.PhloemFoliageGlyphosate

Organo-auxinPhloemFoliage, roots2,4-D

MOATranslocationAbsorption

Note: organo-auxin herbicides require additional record keeping under Florida Pesticide Law

Herbicide Movement

• Foliar Uptake (Phloem):- Glyphosate

• Root Uptake (Xylem):- Hexazinone

• All others:- Primarily by foliar but also with some root uptake

Phlo

em

Xyl

em

Xylem Translocation

Phloem Translocation

Xylem and PhloemTranslocation

Modes of Action

1. Auxin interference (tissue development)

2. Amino acid or protein synthesis interference

3. Photosynthesis inhibitor

Herbicides target biological processes unique to plants

Mode of Action

• Inhibit Photosynthesis- Hexazinone

• Auxin Interference- 2,4-D, Triclopyr

• Amino Acid or Protein Inhibitors - Glyphosate, Imazapic, Imazapyr, Metsulfuron

Other Modes of Action

1. Cell membrane disruptors (contact herbicides) –diquat

2. Growth inhibitors (interfere with cell division) –soil applied / root uptake

3. Pigment synthesis inhibitors (bleachers) – fluridone

4. Lipid / fatty acid inhibitors – effective on grasses and small seeded broadleaf plants

These are seldom used in natural areas weed mngt.

Factors That Affect Herbicide Activity• Rainfall

– Wash-off– Soil moisture

• Drought– Transpiration– Soil moisture

• Wind– Coverage– Stomata closure

• Temperature– Stress/growth

• Humidity– Drying

• Growth stage– Morphology

• Season– Translocation

Factors that adversely affect herbicide activity

• Low relative humidity

• High or cold temperature

• Drought

• Rainfall immediately after application

• High winds

Spray Adjuvants – improve herbicide effectiveness

• Surfactants – allow spray mixes to overcome surface tension and stick to leaves- Nonionic surfactants usually recommended

• Drift control agents – control droplet size• Penetrants – enables a water-based herbicide to

overcome the waxy barrier on many leaf types• Anti-foaming agents – reduce foaming during mixing• Emulsifiers – allow oil-based herbicides to mix with

water• Colorants – keep track of vegetation treated (limit spray

on non-target damage)

EnvironmentalConsiderations

• Wildlife toxicity

• Endangered species– Florida Natural Areas Inventory

• Selectivity– Ability to control the target plant without harming

nontarget plants

Herbicide Toxicity

1. Low activity to higher forms of life

2. Target unique biological processes that are unique to plants- Photosynthesis- Specific growth regulators (auxins)- Amino Acids and Proteins (ALS and EPSP)

---These biological processes or pathways do not occur in animals---

Toxicity (LD50 mg/kg)

1,5819,026Triclopyr ester

192Caffeine

2,574>10,000Triclopyr amine

>5,000>5,620Metsulfuron

>5,000>5,000Imazapyr

>5,000>2,150Imazapic

1,690>10,000Hexazinone

4,300>4,640Glyphosate

>1000>5,6202,4-D amine

Laboratory RatBobwhite quail

• Maintains a list of endangered plants and animals for each county in Florida.

• Contact if there are questions regarding a T or E species in the area to be treated with herbicide

Florida Natural Areas Inventory(FNAI)

SelectivityHerbicide selection

• Broad spectrum herbicides- Control most plants(monocots and dicots)- EX. Glyphosate

• Selective herbicides- Control either monocots (grasses) or dicots (broad-leaved plants)- EX. Triclopyr

• Lots of variability

Herbicide placement

- Best method to control target species

• Method of application• Colorants• Minimize “drift”

– Droplet size»Drift control agents

– Use lowest pressure– Use largest nozzle– Watch wind

Minimizing spray drift:

• Do not spray into wind (spray downwind)

• Use a large-orifice nozzle tip

• Use the lowest possible hydraulic pressure

• Spray during calm (no wind) periods

• Add drift control agents to spray mixture

Application Methods

1) Foliar

2) Basal bark

3) Hack and squirt

4) Cut stump

5) Soil application

Foliar Applications

• Herbicides– Rodeo, Roundup, etc– Garlon 3A– Arsenal

• Surfactants– Penetration– Spreading

• Organosilicones are long chain polymers with good spreading abilities

Minimizing Spray Drift

• Spray downwind (do not spray into wind)

• Do not spray under windy conditions

• Use low spray pressure

• Use a nozzle tip with a large orifice (i.e., larger spray droplets)

• Add drift control agents

Flat Fan Tips Coding

• TP1502

- 15 degrees spray angle

- Delivers 0.2 gallons per minute at 40 psi

• TP2503

- 25 degrees spray angle

- Delivers 0.3 gallons per minute at 40 psi

Basal Bark Applications

• Herbicides– Oil soluble (EC)

• Pathfinder• Garlon 4• Stalker

• Diluents– Vegetable oil

• Most readily breaks down

– Mineral oil– Do not use Diesel fuel

– Toxic to wildlife

Hack and Squirt Applications

• Herbicides– Arsenal– Roundup, etc. – Triclopyr

• Equipment– Machete– Squirt bottles

Cut Stump Applications• Herbicides

– Roundup, Rodeo,etc.

– Garlon 3A– Garlon 4– Arsenal

• Treat as soonas possible(w/i 15 min)

• Cut as levelas possible – less runoff

Inactive xylem

Active xylem

Cambium and phloem(living tissue)

Bark

Herbicides move downward in cut stumpby diffusion

Soil Application

• Granular herbicides applied by hand, spreaders, or blowers.

• Do not apply where the roots of non-target plants may occur.

• Highly water soluble, leach readily, and may contaminate groundwater (refer to label)

Best Treatment Methods(Examples)

• Treatment of a dense stand of torpedograss with no native vegetation nearby:

- Low volume broadcast foliar spray

• Treatment of scattered Brazilian pepper trees among dense native vegetation:

- Basal bark treatment with a hand-held sprayer

Application methods that can selectively control invasive plants

• Basal bark application

• Hack and squirt

• Cut stump

• Low volume foliar application with hand-held sprayer

When would you use broadcast application?

Laws Pertaining to Pesticides

• Federal Insecticide, Fungicide, And Rodenticide Act (FIFRA)– Requires all pesticides to be applied in accordance with

product labeling and that containers are properly disposed of

• Florida Pesticide Law (Chapter 487 FS)– Pesticides are registered and label laws enforced by Florida

Department of Agriculture and Consumer Services

• Florida Department of Environmental Protection– Aquatic plant control permits– Funding for aquatic plant control– Aquatic Plant importation, transportation, transportation, and

cultivation

Final Legal Interpretation of Label

• Florida Department of Agricultural and Consumer Services (FDACS)

Department of Environmental Protection

• Approve permit application of a herbicide to a body of water located on public land

10 minute break

?

Label Interpretation

• Active ingredient

• Directions for use

• PPE

• Mixing instructions, conversions

• Maximum rate per acre

Garlon 4 Label-Active ingredient

-Acid equivalent

-Environmental hazards

-Mixing instructions

-Maximum label rate

-Applications methods

-PPE required

-Safety

How many pounds of triclopyr, expressed as acid equivalent , are contained in one gallon of Garlon 4?• Active ingredient (AI) = chemical in the formulated

product responsible for herbicide effects on plants

• Acid equivalent (AE) = the percentage of acid in the active ingredient

• Product = formulated herbicide under a trade name to include active ingredient + inert ingredients

A.I. vs A.E.

• Active ingredient (AI) – represents the unaltered form of the chemical molecule.

Yet is some cases, the herbicide molecule has been altered by adding some additional characteristics to improve solubility, foliar penetration, and greater translocation without destroying the herbicide property.

• Acid equivalent (AE) – that portion of the original salt or ester molecule that represents the acid form of the molecule

Key: Just know how to find AI and AE on the label

Site Descriptions on Label!

• “Natural areas” does not appear on most labels

• Products registered for use in forestry or noncropland sitesare defensible choices for non-aquatic natural areas

• Label must specify “aquatic use” if it is to be used over standing water.

• Herbicides may be used in wetlands when water is not present unless specifically prohibited by the label

Special Local Need Label (SLN)• Special registration for controlling specific weeds

• Allows a state to further specify how the pesticide is applied

• Applicators must have copy in their possession when applying a SLN herbicide

• Current Example: Metsulfuron (Escort XP) for treating Lygodium microphyllum

Workers Protection Standard (WPS)

• Pertains to people performing tasks related to agricultural activities

• Does not pertain to people performing tasks related to non-cropland sites

• SO, natural area herbicide applicators should follow NON-WPS PPE instructions listed on the label

Note: Know differences between agriculturalapplicators and non-agricultural applicators

REQUIRED Personnel Protective Equipment (PPE)Non-agricultural Sites

• Long-sleeved shirt• Long pants• Shoes• Socks

Note: Chemical resistant gloves are not required (but refer to label)

NOW…..for some “herbicidal”calculations

Two Methods (of many)

• Method 1

- Convert each variable one at a time to get to desired rate or mixture

• Method 2

- Set up equation

- Cross multiply

KEY IS TO PRACTICE WORKING THESE EQUATIONS

Constants Used for Preparing Spray Mixes and Determining Herbicide Rates

• One gallon = 128 ounces

• One gallon = 8 pints

• 1 pint = 16 ounces

• 1% Solution = 1.28 ounces per gallon

• One Acre = 43,560 square feet (ft2)

Other Constants for Tank Mixes• 1.0% / gal = 1.28 oz gallon

• 1.5% / gal = 1.92 oz gallon

• 2.0% / gal = 2.56 oz gallon

• 3.0% / gal = 3.84 oz gallon

• 5.0% / gal = 6.40 oz gallon

• 10.0% / gal = 12.80 oz gallon

Determining Amount of Herbicide Needed for Proportion or % Solution in Spray Solution

• If recommendation is given as herbicide volume per final spray volume– Herbicide volume = (Given herbicide ÷ Given

spray volume ) x spray volume

• If recommendation is given as percent solution– Herbicide volume = Spray volume x (%

recommended ÷ 100)

Calculating Dilutions

• How much Garlon 4 should you add to prepare 4 gal of spray solution equivalent to mixing 20 gal Garlon 4 in 100 gal spray mix?

1) 20 gal ÷ 100 gal = 0.2 (20% herbicide product in spray mix)

2) 0.2 x 4 gal = 0.8 gal (20% herbicide product x 4 gallon spray mix)

3) 0.8 gal x 128 oz/gal=102 oz (convert to oz or pints)

Or 102 oz x 1 pt/16 oz = 6.4 pt

20 gal G4

100 gal spray mix 4 gal spray mix

X gal G41) Set up equation:

2) Cross multiply:

X gal G4(20 gal G4)

100 gal spray mix

(4 gal spray mix)0.8 gal G4

3) Covert gallons to ounces:

(0.8 gal G4) (128 oz)x1 gal

102 oz G4

---Don’t forget to convert to the amount requested in the question---

Calculating Dilutions• How much Garlon 4 should you add to

prepare 4 gal of 1.5% spray solution?

1) 4 gal x 0.015 = 0.06 gal (1.5% product in 4 gallons)

2) 0.06 gal x 128 oz/gal = 7.68 oz (Convert gal to oz)

4 gal x 1.92 oz = 7.68 ozRecall that 1.5% / gal = 1.92 oz per gallon

Spray Volume Per Acre• How many gallons spray mix would be

applied per acre if 60 oz are applied to 400 sq ft?

1) 400 sq ft ÷ 43,560 sq ft/acre = 0.0092 acres(Convert 400 sq ft to acres)

2) 60 oz ÷ 128 oz/gal = 0.4688 gal(Convert 60 oz to gallons)

3) 0.4688 gal ÷ 0.0092 acres = 51 gal/acre(Divide gal by acres to get gal per acre)

60 oz spray mix

400 sq. ft. 43560 sq. ft.

X oz spray mix1) Set up equation:

2) Cross multiply:

X ozspray mix

3) Covert ounces to gallons:

x

(60 oz spray mix) (43560 sq. ft.)

400 sq. ft.6534 oz

6534 oz1 gal

128 oz51 gal

Spray Volume Per Acre

• How many gallons spray mix would be applied per acre if a sprayer delivers 40 oz per minute and 400 sq ft are treated in 5 min?

1) 400 sq ft ÷ 43,560 sq ft/acre = 0.0092 acres

2) 40 oz/min ÷ 128 oz/gal = 0.3125 gal/min

3) 5 min ÷ 0.0092 acres = 543.5 min/acre

4) 0.3125 gal/min x 543.5 min/acre = 170 gal/acre

1) Set up equation, determine minutes to spray an acre:43560 sq. ft.

X min400 sq. ft.

5 min X min 544.5 min

3) Covert ounces to gallons:

1 gal

128 oz170 gal / acrex

21780 oz

acre

2) Determine oz per acre:21780 oz

acre

40 oz544.5 minacre minx

Herbicide Per Tank• How much Roundup (oz) should be

added to a 3 gallon spray tank to apply 7 pints of Roundup per acre for a sprayer that delivers 167 gal per acre?

1) 3 gal/tank ÷ 167 gal/acre = 0.018 acres/tank

2) 7 pt/acre x 0.018 acres/tank = 0.126 pt/tank

3) 0.126 pt x 16 = 2.0 oz

7 pints

167 gal 3 gal

X pints1) Set up equation:

2) Cross multiply:

X pints

3) Covert pints to ounces:

x

(7 pints) (3 gal)

167 gal0.1257 pints

0.1257 pints16 oz

1 pint2.0 oz

Determining Amount of Herbicide NeededSurface Area Applications

Herbicide needed =

recommended pounds per acre x surface area to be treated

or

recommended gallons per acre x acres to be treated

Example

How much Velpar ULW is required to treat an area that measures 270 feet by 470 feet with VelparULW (granules) at a rate of 2 pounds product per acre?

1) Determine acreage:Acres = 270 ft x 470 ft ÷ 43,560 ft2 pr acreAcres = 2.9 acres

2) Determine herbicide needed2.9 acres x 2 lbs per acre = 5.8 lbs

QUESTIONS