Box Elder Trees

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pollen library

Maple, Box Elder (Acer)

Maple, Box Elder Genus Details

Maples are trees and shrubs with worldwide distribution, of which 13 species are native to US. Almost all maples are deciduous with distinct, palmate leaves (with parts diverging from a common base, as the fingers of a hand). The leaf is used as a logo for the Toronto Mapleleafs hockey team. Fruit are paired, winged seeds, known as samara. Many maples are popular for ornamental and street plantings. Acer negundo (box elder) differs from other maples in that its leaves are pinnately compound (separate leaves diverge from one central stem), and in that it has male and female flowers on separate trees that are entirely wind-pollinated. Trees reach 30-100 feet in height and 2-4 feet in diameter. In the U.S. flowering usually occurs in early spring through April or May, but can begin in January and February for sugar maples and other species, with a few species in W. U.S. flowering in June and July.

Maple, Box Elder Allergy Info

All maple species are potentially allergenic. Box elder, which is primarily wind-pollinated, has significantly allergenic pollen. Silver maple has a secondary allergic importance except where very abundant. The other maples appear to cause fewer problems.

Maple, Box Elder Pollen Description
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Grains vary in shape from prolate to spheroidal; the amb rounded-triangular with convex sides, and 3-colpate or 3-colporate. The colpi are long with tapering, blunt or rounded ends. Pollen grains of Acer negundo (box-elder) have a distinct rugulate-undulating sexine.
The pollen grains vary in size, depending on the species and can vary in size from 30-51 micrometers x 20-36 micrometers to 22-26 x 20-36 micrometers in diameter.

Species in This Genus

Allergenicity Legend:
Mild Allergen Mild Allergen | Moderate Allergen Moderate Allergen | Severe Allergen Severe Allergen | Allergy Test Allergy Test Available
Maple, Box Elder (Acer) is a genus of the ACERACEAE family.
This genus includes the following allergenic species:
Big-Leaf Maple (Acer macrophyllum)
Black Maple (Acer nigrum)
Box Elder, Ash-Leaf Maple (Acer negundo)
Canyon Maple (Acer grandidentatum)
Japanese Maple (Acer palmatum)
Mountain Maple (Acer spicatum)
Norway Maple (Acer platanoides)
Red Maple (Acer rubrum)
Rocky Mountain Maple (Acer glabrum)
Silver Maple (Acer saccharinum)
Striped Maple (Acer pensylvanicum)
Sugar Maple (Acer saccharum)
Sycamore Maple (Acer pseudoplatanus)
Tatarian Maple (Acer tataricum)
Vine Maple (Acer circinatum)