Chrysoteuchia topiarius
In 3 days ~20% in a week ~30%
Chrysoteuchia topiarius, the topiary grass-veneer moth, subterranean sod webworm or cranberry girdler, is a moth of the family Crambidae. The species was first described by Philipp Christoph Zeller in 1866. It is found in most of North America.
The wingspan is 17–20 mm. Adults are on wing from late June to early August in one generation per year. The larvae feed on a wide range of plant, including mostly grasses. As larvae, they also feed at the base of cranberry vines, which results in irregular brown and dead patches, thus giving it the name the cranberry girdler. Wikipedia →
| # | Park | Country | Daily sighting probability |
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More parks will be added in future updates.
With luck
About 10% of wildlife watchers report a Topiary Grass-Veneer sighting in Portland on a given day, based on 59 verified sightings from GBIF citizen-science data. It is the 122nd most-seen of the 507 insects we can rate there. Over three days the chance rises to about 20%, and over a week to about 30%, if each day is a fresh chance.
June and July
In those months about 10% of wildlife watchers report a Topiary Grass-Veneer in Portland on a given day, against under 5% in August to May, the lowest months. Those are among Portland's driest months, with about 35 mm of rain a month against 250 mm in December.
Among the best
Of the 11 cities where we can rate Topiary Grass-Veneer sightings, Portland ranks 2nd at about 10%, level with the leaders once rounded. The best odds are in Edmonton (Canada, about 10%).
Same family: Crambidae
The closest relatives of the Topiary Grass-Veneer that you can see in Portland (family Crambidae, Crambid Snout Moths) are Inornate Pyrausta Moth (about 10%) and California Pyrausta Moth (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Topiary Grass-Veneer is recorded against all the insects logged in Portland (59 verified sightings), calibrated against known sighting rates. Figures are rounded to the nearest 10% because citizen-science data supports honest approximations, not decimals, and months with records from fewer than five people show "—". How it works.
