Eriosoma americanum
In 3 days ~10% in a week ~20%
Eriosoma americanum, the woolly elm aphid, is an aphid native to North America, found where Saskatoon (Amelanchier alnifolia) and American elm (Ulmus americana) trees are established. The aphid feeds on the Saskatoon in late spring through fall, and the American elm during both early spring and late fall.
Symptoms of American elm infestations include curled elm leaves, later accompanied by masses of visible dark areas and cottony masses. As with other aphids, honeydew may be found on infected leaves, excreted by the aphids after feeding on the plant's sap. Wikipedia →
| # | Park | Country | Daily sighting probability |
|---|
More parks will be added in future updates.
| # | City | Country | Daily sighting probability |
|---|---|---|---|
| 1 | Washington | 🇺🇸 United States | |
| 2 | New York City | 🇺🇸 United States |
Rare
Under 5% of wildlife watchers report a Woolly Elm Aphid sighting in Washington on a given day, based on 18 verified sightings from GBIF citizen-science data. It is the 851st most-seen of the 1807 insects we can rate there. Over three days the chance rises to about 10%, and over a week to about 20%, if each day is a fresh chance.
Any time of year
In every month with enough records, under 5% of wildlife watchers report a Woolly Elm Aphid in Washington on a given day, so our monthly data shows no clear season.
Yes
Of the 2 cities where we can rate Woolly Elm Aphid sightings, Washington has the highest daily chance: under 5%. Next come New York City (United States, under 5%).
Same family: Aphididae
The closest relatives of the Woolly Elm Aphid that you can see in Washington (family Aphididae, Aphids) are Oleander Aphid (about 10%), Witch-Hazel Cone Gall Aphid (about 10%) and Beech Blight Aphid (about 10%), with each one's daily chance of a sighting.
GBIF citizen-science records
It is estimated from how often the Woolly Elm Aphid is recorded against all the insects logged in Washington (18 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.
