Smoke from Canadian wildfires again plagued portions of the northern United States on July 16, prompting air quality alerts from Illinois to Maine.

Ivy said there is anecdotal evidence that shows birds are being impacted by wildfire smoke, but there has never been research on the effects. One wildfire wouldn't have any adverse effect on birds, ...

The haze can reflect and interfere with sunlight, which could disrupt photosynthesis. How that affects yields depends on the ...