About this data

What this site shows

• Planned applications. The pesticide applications Montgomery Parks lists on its public schedule: which park, which part of it, the date window, the time window, and the products named.
• Past applications. What Montgomery Parks staff and contractors reported applying, from the department’s semi-annual pesticide (IPM) reports, January 2021 through June 2026.
• Hazard information. What each product’s EPA registration and label say: its signal word, whether it is a restricted-use pesticide, and the hazards the label warns about.
• Context. Plain-language explainers for each active ingredient, stream and well tests in the county, and county-wide totals from the Maryland Pesticide Survey.

Sprayed? only collects and maps published information. It is not run by, and does not speak for, Montgomery Parks.

Sources

Counts below are as of October 2026.

How to read it

Statuses

• Happening today: today falls inside the planned date window (or is one of the listed days).
• Coming up: the window starts after today.
• Recently done: the window ended in the last 14 days.
• Past 12 months: applications reported in Parks’ semi-annual reports during the last year.

“Today” follows Eastern time.

Signal words

Every registered pesticide label carries a signal word for how harmful the product is to people in the short term, as sold (before mixing). From lowest to highest:

1. CCaution: slightly toxic, or slightly irritating to eyes or skin.
2. WWarning: moderately toxic, or moderate eye or skin irritation.
3. DDanger: highly toxic, or corrosive (can permanently damage eyes or skin).

A few minimum-risk products have no signal word. A product the site couldn’t match to one EPA registration shows as unknown (?).

Restricted use

EPA classifies some products as restricted-use pesticides: only certified applicators, or people under their direct supervision, may buy or apply them. Three products in this data are restricted use: Onyx Pro, Oxadiazon 2G and TREE-äge.

Hazard, not risk

Label warnings say what a product can harm, such as “toxic to fish”. They don’t say how likely harm is at a given park. Risk depends on how much was applied, where, and who or what was exposed, and the schedule and reports don’t include amounts.

Stream and well tests

A “detection” means a lab reported a measured amount. Each lab and decade has its own reporting limit, the smallest amount it can reliably measure, so “not detected” means “below that lab’s limit”, not “none at all”. A detection can’t be traced to park spraying: the same chemicals are used on farms, lawns, golf courses and in pet and household products.

Limits and caveats

• Plans can change. Montgomery Parks notes that dates can change or be canceled due to weather. A planned application is not confirmation that spraying happened; only the later semi-annual report shows what was applied.
• Rows can name several products. A schedule row may say one product “and/or” another, and 178 report records list more than one product. The site shows every product named, even if only one was used.
• Some product names don’t match. Reports sometimes use brand lines, generic names, typos or names cut off in the PDF. In the reports, 202 of 2,361 product mentions (28 names, such as “Prosecutor” or “Wasp and Hornet spray”) have no identified active ingredient, and 73 product names couldn’t be matched to one EPA registration. These show as unknown rather than guessed.
• Some parks aren’t on the map. 16 of 193 parks in the reports (54 records) couldn’t be located, so they appear in lists but not as pins.
• Report dates have no year. The year is inferred from the report period. Some older reports are scans; their text was read by OCR and checked by hand, but errors are possible.
• Only Montgomery Parks is covered. Spraying on private property, farms, school grounds, county roadsides and homeowners’ association land isn’t published here and isn’t on this site.

Notes on the reports

A few report entries stand out when compared with label or EPA information. They are listed here as recorded in the reports, without drawing conclusions:

• MSMA (Target 6 Plus) is recorded on two ballfields at Ridge Road Recreational Park in September 2025. EPA canceled MSMA uses on athletic fields and parks in 2009.
• LI 700, a spray additive, is recorded with an algaecide for pond and shoreline algae work (three records, 2025–2026). Its safety data sheet says it is not intended for use in aquatic settings.
• Clethodim, which controls grasses only, appears in 21 records whose target is “Canada Thistle, Johnsongrass”. Thistle is a broadleaf weed; in each of those records clethodim is listed together with clopyralid, which is used on thistle.