Utah Pesticide Applicator Ornamental & Turf Exam: Practice Test & Licensing Guide

You are calibrating a boom sprayer with nozzles spaced 20 inches apart, traveling at 4 mph. Each nozzle puts 0.2 gallon into a catch cup in 30 seconds. Using the manual's formula, what is the sprayer's output in gallons per acre (GPA)?

Answer: 29.7 GPA

First convert the catch to gallons per minute (GPM): 0.2 gallon in 30 seconds × 2 = 0.4 GPM. The formula is GPA = (GPM × 5,940) ÷ (mph × nozzle spacing in inches), so (0.4 × 5,940) ÷ (4 × 20) = 2,376 ÷ 80 = 29.7 GPA. Plugging in 0.2 without converting to a full minute gives 14.9. Doubling twice (using 0.8) gives 59.4. Using the 136 constant gives 0.68, but that is gallons per 1,000 sq ft, not per acre.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 6: Application Equipment and Techniques — Calibration Examples: Boom Sprayers

You calibrate a compressed-air sprayer by marking off an 18.5 ft × 18.5 ft square and adding 64 ounces of water to the empty tank. After spraying the square evenly, 22 ounces are left in the tank. What is the sprayer's delivery rate?

Answer: 42 gallons per acre

In the 18.5 ft × 18.5 ft method, the number of ounces sprayed on the square equals the gallons per acre. Ounces sprayed = 64 − 22 = 42, so the sprayer delivers about 42 GPA. The 22 answer uses the leftover water instead of the water sprayed. The 64 answer ignores what was left in the tank. Adding the two (86) has no meaning.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 6: Application Equipment and Techniques — A Procedure for Calibrating Compressed Air Sprayers

In late May a customer shows you small crabgrass seedlings coming up in thin turf along the sidewalk edge. No preemergent was applied this spring. What is the best plan?

Answer: Spot-treat the seedlings with a labeled postemergent now; use a preemergent next spring

Preemergence herbicides act on seeds as they germinate, so they do nothing to crabgrass that has already emerged. Emerged weeds need a postemergence product, which works best on small, immature plants. Crabgrass germinates when soil reaches about 60°F, and sidewalk edges warm first. Next year's preemergent should go down before that. Spraying after the plants have gone to seed gives no long-term benefit for an annual.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 9: Weed Management — Select Appropriate Chemical: Preemergent/Postemergent

Two days after you sprayed a dicamba-containing broadleaf product on a lawn on a 92°F, low-humidity afternoon with almost no wind, the neighbor's tomatoes in the vegetable garden next door show curled, twisted leaves. What is the most likely way the herbicide got there?

Answer: Volatilization: it turned to vapor and moved off-site

Dicamba is more prone to volatilization than many pesticides, especially above about 85°F with low humidity. A product can volatilize from spray droplets or from residues after application and move off-site as vapor even when there is little wind. Photodecomposition and microbial breakdown destroy the pesticide rather than moving it. Leaching moves material downward, not into the leaves of a neighboring garden. Allowing off-site drift that damages plants is an unlawful act in Utah.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 3: Pesticides in the Environment — Environmental Fate of Pesticides: Volatilization Drift; Impacts Influenced by Weather Conditions

A lawn normally kept at 3 inches has grown to 4½ inches during a wet week. Following the one-third rule, what is the lowest height you should mow it to today?

Answer: 3 inches

Remove no more than one-third of the leaf blade at a mowing. One-third of 4½ inches is 1½ inches, so the shortest cut is 4½ − 1½ = 3 inches. The 1½-inch answer is the amount to remove, not the height to leave. Cutting to 2 or 2½ inches would remove more than a third and scalp the turf, making it more prone to disease and weeds.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 4: Integrated Pest Management (IPM) — Proper Cultural Practices: Mowing

Which three factors make up the disease triangle that must all be present for a biotic disease to develop?

Answer: A pathogen, a susceptible host and a favorable environment

The disease triangle needs a causal agent (pathogen), a susceptible host and favorable environmental conditions, all at the same time for a certain period. Remove or change any one side and disease will not develop. Fungicides block the pathogen, resistant varieties replace susceptible hosts, and cultural practices change the environment. Vectors matter for some pathogens but are not one of the three sides.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 10: Plant Diseases and Disorders — Disease Triangle

A label you plan to use in June carries an Endangered Species Restrictions statement, and an active EPA bulletin exists for that county. Which statement is correct?

Answer: Print it and keep it with the application record; no need to carry it

If the label has an Endangered Species Restrictions statement, the applicator must check EPA Endangered Species Bulletins for the county. Bulletins can be accessed up to 6 months before the month of application (January at the earliest for a June job). If an active bulletin exists, you must print a copy and keep it with the application record, but it does not need to be in your possession during the application.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 2: Laws and Regulation — Endangered Species Act of 1973 (ESA)

You arrive to spray a residential lawn. No one answers the door, a bedroom window facing the lawn is open, and laundry is on the line. What should you do?

Answer: Call the customer to tell them the application must be rescheduled

Before applying at a residence, do a visual check for open windows, vehicles, pets, people, pools or bird baths, laundry on a line, personal property and neighbors. If no one is home and windows are open or clothes are on the line, the manual says to call the customer and let them know you need to reschedule. At townhomes you may need to skip that area and note it on the work order. Entering or altering the property yourself is not the guidance.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 7: Professionalism, Safety, and Human Health — Prevent and Minimize Hazards: Residences

Why does the manual say fall is the best time to treat many perennial weeds with a systemic herbicide?

Answer: Sugars move down to the roots, carrying the herbicide

Roots store carbohydrates made in the leaves during late summer and fall, and in spring the sugars move back up to the buds. Because food reserves move down in fall, herbicides applied then are more likely to be translocated to the roots, giving longer-term control. This is why fall is the recommended timing for dandelions.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 8: Plant Biology Basics — How Plant Biology Influences Pesticide Application Success: Pesticide Transportation and Translocation; Plant Parts: Roots

You are scheduled to spray a broadleaf herbicide on a lawn next to a neighbor's vegetable garden. Which forecast conditions does the manual list as reasons to postpone?

Answer: Rain, wind, or temps over 80°F with low humidity

The manual lists three reasons to postpone: forecast rain, windy conditions, and temperatures above 80°F with low humidity. Rain can wash product off, wind causes particle drift, and heat with low humidity causes volatilization. Next to a vegetable garden, drift or vapor injury would also be an unlawful act. Check the label for how long the product needs before rain.

Reference: Ornamental and Turf Pesticide Safety Study Guide (UDAF, Category 3), Chapter 5: Site Evaluation — Site Evaluation at Time of Application: Weather Conditions