epa_ppls: narrow row-crop filter to corn/soy/wheat only

App focus is corn, soybeans, and wheat. Dropping the broader
US-row-crops allowlist (cotton/rice/sorghum/milo/barley/oats/rye/
sunflower/peanut/sugar-beet/dry-bean/canola/alfalfa).

Empirical impact (random N=100 sample): broad list matched 17/100
products, narrow list matches 16/100 — only 6% reduction, because
corn/soy/wheat dominate ag-chem registrations so thoroughly that
products registered for cotton/sorghum/etc. are almost always
co-registered for one of corn/soy/wheat. One sampled product was
dropped: a peanut-only herbicide (2749-614).

Verified live: 524-475 Roundup + 524-591 Warrant kept (CORN/SOYBEAN
sites); 2749-614 AG36448 (PEANUTS only) correctly filtered.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scrape/sources/epa_ppls.py

@@ -83,23 +83,17 @@ MAX_RETRIES = 4
 # "OATS" naively matches "SHIPS, BOATS, SHIPHOLDS"; bare "RICE" matches
 # "LICORICE"; bare "RYE" matches "FRYER".
 #
-# Scope = the major US row + small-grain + oilseed + sugar/fiber crops the
-# farmer-advisor consumer cares about. Alfalfa included as a common rotation
-# crop; sweet/seed corn included alongside field corn.
+# Scope = the three crops the farmer-advisor consumer focuses on: corn,
+# soybeans, and wheat. Sweet/seed/pop corn included alongside field corn.
+# Empirically (random N=100 sample, 2026-05-23): this narrow allowlist
+# matches ~16% of all PPLS products and only loses ~6% of the broader
+# "all US row crops" hit set, because corn/soy/wheat dominate ag chemistry
+# registrations — almost every product registered for e.g. cotton or
+# sorghum is co-registered for at least one of corn/soy/wheat.
 ROW_CROP_KEYWORDS = (
     "CORN", "MAIZE", "POPCORN",
     "SOYBEAN", "SOYBEANS",
-    "COTTON",
     "WHEAT",
-    "RICE",
-    "SORGHUM", "MILO",
-    "BARLEY", "OATS", "RYE",
-    "SUNFLOWER", "SUNFLOWERS",
-    "PEANUT", "PEANUTS",
-    "SUGAR BEET", "SUGAR BEETS",
-    "DRY BEAN", "DRY BEANS", "FIELD BEAN", "FIELD BEANS",
-    "CANOLA", "RAPESEED",
-    "ALFALFA",
 )
 _ROW_CROP_PATTERNS = tuple(
     re.compile(rf"\b{re.escape(kw)}\b", re.IGNORECASE)