Birch
If it’s spring and you’re sneezing, those timber might be part of the problem. They develop throughout the continental U.S., besides in the southernmost and westernmost states, and their pollen could be very likely to trigger allergies. They’re frequently planted in yards and other landscaping due to the fact humans like the manner they look -- the telltale white bark makes them easy to identify.
Elm
Cedar
Oak
Pine
Poplar
Walnut
Ragweed
Bermuda grass
Bluegrass
Nettle
Sagebrush
Tumbleweed
Lamb's quarters
English plantain