
Green ash
Fraxinus pennsylvanica
Moderate today, mostly grass pollen.
Last updated July 1, 2026
Grass pollen is the main driver in Centennial today, sitting at a moderate level and pushing the overall index to moderate. Tree pollen has dropped to very low, so species like Ash, Linden, Pyrus, Picea, and Pine are contributing little at this point in the season. The five-day forecast holds steady, with grass remaining moderate and tree counts staying very low throughout. This pattern is typical for late June, when grasses dominate after the spring tree peak has passed. Weed pollen data is unavailable today, so that category isn't reflected in the current reading.
Every dot is a tree near Centennial, colored by how allergenic it is. Click one for its details, and zoom in for a closer look.
The local tree genera behind today's pollen near Centennial. Each bar is that genus's share of the tree pollen.
58 pollen-relevant trees nearby drive today's tree-pollen reading.
Get to know the tree types growing around Centennial: what each looks like, how allergenic it is, and when it blooms.

Green ash
Fraxinus pennsylvanica

White ash
Fraxinus americana

Austrian pine
Pinus nigra

Littleleaf linden
Tilia cordata

Ponderosa pine
Pinus ponderosa

Honeylocust
Gleditsia triacanthos

Freeman maple
Acer freemanii

Norway maple
Acer platanoides

American linden
Tilia americana

Honey locust
Gleditsia triacanthos

Linden
Tilia

Silver maple
Acer saccharinum

Flowering pear
Pyrus calleryana

Scotch pine
Pinus sylvestris

Northern red oak
Quercus rubra

Northern hackberry
Celtis occidentalis