Get aeroallergen readings for Hickory or Walnut.

Important genera:

Hickory/Pecan (Carya) and Walnut (Juglans)

Tree pollen is dominant in the spring.
Hickory/Pecan pollen season extends from April to June.
Walnut pollen season extends from April to May.

Hickory, Pecan and Walnut trees in Missouri:

• Water or Bitter Hickory (Carya aquatica)
• Bitternut Hickory (Carya cordiformis)
• Pecan (Carya illinoiensis)
• Shellbark Hickory (Carya lacinosa)
• Shagbark Hickory (Carya ovata)
• White Hickory (Carya tomentosa)
• White Walnut or Butternut (Juglans cinerea)
• Black Walnut (Juglans nigra)

Facts about Hickory, Pecan and Walnut

• Hickory, pecan, and walnut trees have compound leaves with lance-shaped leaflets.
• The Black walnut is much oilier and richer tasting than that of the English walnut found in grocery stores.

Hickory, Pecan and Walnut Allergenicity

• The pollen of all these trees is large and does not travel far. However, in areas where the trees are cultivated commercially, heavy exposure to the pollen can cause allergy symptoms.
• Walnut pollen is generally considered to be moderately allergenic.
• The western species of walnut (in California) is thought to be a more important cause of allergic sensitization than the Black walnut.