Moderate Pollen in Ontario, CA

About pollen in Ontario

Weed pollen is the main story in Ontario today, sitting at a moderate level that sensitive individuals will likely notice. Grass is present but at a very low level, unlikely to cause much trouble, and tree pollen is essentially absent right now. Looking ahead, this pattern is expected to hold steady over the next several days, with weed pollen remaining moderate and grass staying low. This lines up with the season, as late summer into fall is typically prime time for weeds like ragweed rather than tree pollen. Local trees such as liquidambar, cercis, mesquite, and maple had their turn earlier in the year and are quiet for now, so anyone with weed sensitivities should expect similar conditions through the week.

What to do today

• It's important to shower and wash your hair after spending a lot of time outdoors.
• When spending time outside, use sunglasses and a cap to keep pollen out of your face and eyes.
• Wash clothes worn outdoors to remove any remnants of pollen grains.
• If possible, wear glasses instead of contact lenses.
• Did you hang any laundry outside? Now is a good time to hang clothes indoors or use a dryer if possible.

Tree map

Every dot is a tree near Ontario, colored by how allergenic it is. Click one for its details, and zoom in for a closer look.

Top tree-pollen sources

The local tree genera behind today's pollen near Ontario. Each bar is that genus's share of the tree pollen.

Meet the trees near you

Get to know the tree types growing around Ontario: what each looks like, how allergenic it is, and when it blooms.

American sweetgum

Liquidambar styraciflua

Allergenicity 2/4Blooms spring

Ornamental pear

Pyrus calleryana

Allergenicity 1/4Blooms spring

Silver maple

Acer saccharinum

Allergenicity 3/4Blooms spring

Tulip tree

Liriodendron tulipifera

Allergenicity 1/4Blooms spring

Chinese elm

Ulmus parvifolia

Allergenicity 3/4Blooms spring

Canary island pine

Pinus canariensis

Allergenicity 1/4Blooms spring

Aleppo pine

Pinus halepensis

Allergenicity 1/4Blooms spring

Coast live oak

Quercus agrifolia

Allergenicity 4/4Blooms spring

Leaf plum purple

Prunus cerasifera

Allergenicity 1/4Blooms spring

London plane

Platanus acerifolia

Allergenicity 4/4Blooms spring

Evergreen pear

Pyrus kawakamii

Allergenicity 1/4Blooms spring

Holly oak

Quercus ilex

Allergenicity 4/4Blooms spring

London plane bloodgood

Platanus acerifolia

Allergenicity 4/4Blooms spring

Shamel ash

Fraxinus uhdei

Allergenicity 4/4Blooms spring

Glossy privet

Ligustrum lucidum

Allergenicity 2/4Blooms spring

Japanese black pine

Pinus thunbergiana

Allergenicity 1/4Blooms spring

Common questions

What is the pollen count in Ontario, CA today?

Ontario, CA is at a moderate 3 out of 5 on the Universal Pollen Index today, driven mainly by weed pollen. The five-day outlook holds steady around 3 of 5.

Is weed pollen high in Ontario, CA right now?

Weed pollen is moderate today at 3 of 5, and it's in season now. Sensitive people may notice symptoms.

What plants are causing allergies in Ontario, CA?

The main sources right now are Liquidambar, Cercis, Prosopis, Pithecellobium, and Maple. Elm (Ulmaceae (the Elm family), Two distinct seasons, late winter to early spring, and late summer to fall (species dependent)) is actively pollinating.