The maple tree -- more specifically, the ashleaf maple or box elder tree -- is another plant that produces potent allergens. Other species of maple, like the red, silver, and sugar varieties, also trigger allergies. But the ashleaf maple is the worst offender. Only the male trees produce the pollen allergen. These trees favor a lot of light and rich, moist soil. Maples are popular for their timber, sugar and syrup.
- Appearance: Ashleaf maples are small- to medium-sized trees. They grow from 30 to 50 feet high, with a typical trunk diameter of about 4 feet. Blooms grow in small bunches, have no petals, and are greenish-yellow.
- Peak time:Maple trees flower and release pollen in the early spring.
- Location: Maples are mostly found along streams and in the woods of the Eastern United States and Canada, and midwestern North America.