The American College of Allergy, Asthma & Immunology (ACAAI) calls it "blanching." Hives are not contagious or life-threatening, but they can become chronic
So, if you find a strain that consistently gives you a headache, it might be time to try a different one
"As the day goes on and the sun moves across the sky, these leaves are more tightly clustered together on the stalk and can be in direct sunlight for a much shorter period of time before they enjoy shade from their neighbor, or provide shade to neighboring leaves," he says
On file with the National Park Service Cultural Resources Office of Interpretation and Education, Washington, DC
We do expect over time, smoking to die out almost completely, said Chris Whitty, chief medical officer for England, speaking on BBC Radio 4