lawn
Pesticide Basics & Pest Identification
Signal Words (front-panel, mandated by EPA; communicate acute toxicity)
Caution – product is slightly toxic; LD generally > 500 \,\text{mg/kg} for oral exposure.
Warning – product is moderately toxic; LD .
Danger / Danger-Poison (skull-and-crossbones) – product is highly toxic or corrosive; LD < 50 \,\text{mg/kg}.
Practical implication: choose lowest-toxicity material that will provide adequate control, and adjust PPE accordingly.
Adjuvants (tank-mix additives that modify spray characteristics)
Surfactants – reduce surface tension ⇒ better spreading, wetting, and sticking.
Oils/crop oils – improve penetration through waxy cuticles.
Drift control agents – increase droplet size, reduce off-target movement.
Contact vs. Systemic Pesticides
Contact – remain on treated surface; kill only when pest or pathogen touches residue.
Advantages: fast knock-down, reduced potential for phytotoxicity inside plant.
Limitation: requires thorough coverage, no internal protection.
Systemic – absorbed by plant/host and translocated (xylem or phloem) or absorbed through insect cuticle.
Provides internal protection and some residual activity; may control pests in hidden sites.
Must consider potential for phytotoxicity and pollinator exposure (e.g., neonicotinoids).
Key Toxicological & Plant Health Terms
LD – lethal dose that kills 50 % of a test population (usually rats); expressed as body weight.
Phytotoxicity – any chemical injury to plants (leaf burn, chlorosis, stunting); often due to wrong dosage, environmental stress, or sensitive species.
Formulation Types
Dry: Wettable Powder (WP), Water-Dispersible Granule (WDG/DF) – require agitation, can be abrasive to pumps.
Liquid: Emulsifiable Concentrate (EC) – oil-based product that forms an emulsion when added to water; may cause rubber hose degradation.
Insect & Weed Biology Essentials
Insect body regions – head (sensing/feeding), thorax (locomotion), abdomen (digestion/reproduction).
Metamorphosis
Complete: egg → larva → pupa → adult (e.g., beetles, butterflies) – IGRs commonly target immature larval stages.
Incomplete: egg → nymph → adult (e.g., true bugs, grasshoppers).
Weed Categories
Monocot – one cotyledon; parallel veins (e.g., grasses).
Dicot – two cotyledons; net veins (e.g., plantain).
Annual vs. Biennial vs. Perennial; reproduction via seed, stolons, rhizomes.
Reasons for Accurate Pest Identification
Ensures correct selection of control tactic, reduces unnecessary pesticide use, avoids resistance and non-target damage.
Vector – any organism (e.g., mosquito, tick) that transmits a pathogen; key for public health considerations.
Typical Turf Insect Symptoms
Loose sod, brown patches, birds pecking, visible grubs/larvae.
Labels, Laws, Math & Environment
“The Label is the Law” – federal and state enforceability under FIFRA; any off-label use is illegal.
Key Label Sections
Front Panel: product name, active ingredient %, signal word, EPA Reg. No.
Directions for Use: safety, PPE, REI, site restrictions, application rates.
EPA Registration Number – unique identifier linking product to its approved formulation and label; critical when checking for state registration or reporting spills.
Site Specificity – it is unlawful to apply to a crop/site not listed.
Basic Turf Application Math
Conversions: .
Example 1: 1.5 gal/1,000 ft ⇒ .
Example 2: Sprayer delivers 25 gal to 10,000 ft ⇒ .
Example 3: Rate 2 oz/1,000 ft; treat 5,000 ft ⇒ .
Area Formulas: rectangle ; circle .
Environmental Fate & Timing
Leaching – downward movement through soil profile; greatest with sandy soils, heavy irrigation.
Volatilization – evaporation into air; higher with high temps, low humidity, high winds.
Runoff Protection – avoid application before heavy rain, maintain vegetative buffers, follow slope/set-back rules.
Drift Indicators – odor complaints, off-species injury, visible residue.
Restricted Entry Interval (REI) – time that must elapse before unprotected people can re-enter; listed in Directions for Use.
Integrated Pest Management (IPM) & Turfgrass Science
Core IPM Goal – maintain pest populations below the action threshold with minimal environmental/pesticide impact.
Four Control Categories
Cultural – e.g., mowing at correct height ( in for cool-season lawns), balanced fertilization, irrigation scheduling.
Mechanical/Physical – hand weeding, thatch removal, aeration.
Biological – predators, parasites, endophyte-enhanced grasses.
Chemical – pesticides as last resort, timed to pest life stage.
Monitoring – routine scouting, degree-day models, record keeping.
Threshold – pest density at which cost of damage equals cost of control.
Wisconsin Cool-Season Turf Overview
Kentucky bluegrass – common home lawn; rhizomes ⇒ self-repair.
Perennial ryegrass – fast germination; good wear but poor shade.
Tall fescue – deep roots, drought tolerant; coarse texture.
Fine fescue – shade tolerant; lower fertility need.
Disease & Stress Factors
High humidity, poor airflow, excess N, thatch >0.5 in, prolonged leaf wetness.
Necrotic Ring Spot – arcs of dead turf; linked to K deficiency & stress.
Thatch – excessive organic layer blocks water & pesticide penetration; dethatching restores infiltration.
Endophytes – fungal symbionts in rye/fescues that deter surface-feeding insects (e.g., chinch bugs); do not control grubs.
Fertilizer & Application Restrictions (Wisconsin-Specific)
Phosphorus Ban – no P unless establishing turf or correcting documented deficiency.
Buffer Zones – no fertilizer within 20 ft of water body (may reduce to 5 ft with deflector shield).
Posting Requirement – sign with “Keep Off the Grass” symbol, date & time; must remain ≥12 h.
Frozen Soil Rule – no fertilizer/pesticide on frozen or snow-covered ground.
Hard Surface Cleanup – sweep granules from walks/driveways immediately.
Spill Response & Safety (Three C’s)
Control – stop the leak, shut valves, right overturned containers.
Contain – use absorbent materials (kitty litter, pads), create dikes.
Clean Up – collect waste in sealable drums; label for disposal.
Large spill (trigger volumes per DNR) ⇒ contact Wisconsin DNR spill hotline immediately.
Calibration & Application Equipment
Calibration – series of measurements/adjustments ensuring delivery of labeled rate; should be done before every job or after equipment changes.
Output Rate Factors – operating speed, nozzle size/type, pressure.
To reduce high output: increase walking speed, decrease pressure or nozzle flow rate.
Catch Test – spray into graduated container for known time/distance; compare to target output.
Nozzle Selection
Flat-fan – uniform distribution for broadcast herbicides.
Cone – finer droplets for contact fungicides/insecticides; higher drift risk.
Boom Height – maintain in above canopy for even overlap.
Drift Management – spray when wind <10 mph, use coarse droplets, keep pressure low, add drift agents if allowed.
Cleaning – triple-rinse equipment after each use; avoid cross-contamination.
Regulatory Compliance & Worker Safety
Wisconsin Oversight – DATCP enforces state pesticide/fertilizer laws.
Certification
License required for any restricted-use pesticide (RUP) or for-hire applications.
Recertification cycle: 5 years.
Minimum age: 16 (21 to supervise).
Worker Protection Standard (WPS) – mandates training, PPE, de-contamination, posting.
Recordkeeping – keep records ≥2 years: date, time, location (address or GPS), product name & EPA Reg. No., rate, area treated, temperature/wind, applicator ID.
Service Containers – secondary jugs must display product name, active ingredient(s), and signal word.
Back-Siphoning Prevention – maintain air gap or install anti-siphon device when filling tanks.
Storage – locked, ventilated, dry, fire-resistant; segregate herbicides from insecticides/fungicides to prevent odor/label contamination.
Transportation – secure upright, block & brace; carry SDS and emergency contact list.
Turf Management Scenarios & Specialty Topics
Warm- vs. Cool-Season Turf
Warm-season (e.g., Bermudagrass) thrive at ; winter-kill in WI.
Invasive Species – non-native plants displacing natives; e.g., ground ivy (creeping Charlie) in lawns.
Pre-Emergent Crabgrass Timing – late April–early May; correlate with forsythia bloom or soil temp .
Weed-and-Feed in Drought – delay; herbicides increase phytotoxicity on moisture-stressed turf.
Moss Causes – shade, compaction, acidic soil (pH <6); aeration + liming + pruning trees.
Frost Seeding – broadcast seed onto partially frozen ground in late winter; freeze-thaw pulls seed into soil.
Aeration – removes soil cores, alleviates compaction, improves infiltration and gas exchange.
Ideal Soil pH – for nutrient availability.
Numerical Quick-Reference
Recommended mowing heights: in (cool-season lawns).
Action threshold concept: pest density at which expected loss = control cost.
Posting duration: ≥12 h after application.
Passing exam score: 70 % (≥56 correct of 80 questions, if exam has 80 items).
Personal & Exam Preparation Tips
Always read the label before mixing or applying – even familiar products may have revised instructions.
Bring to state exam: PAT (Pesticide Applicator Training) number, government ID, basic (non-programmable) calculator.
Misapplication Consequences – fines, license suspension, civil liability for drift/damage.
PPE Essentials – chemical-resistant gloves, goggles/face shield, long sleeves, long pants, closed-toed footwear; upgrade to respirator if label requires.
Regular Calibration – primary safeguard against over/under application; document calibration dates for inspection. re