The first frost of autumn marks the arrival of some short-term seasonal health hazards that bear watching.

• During this time of fall yard fix-ups, be alert for landscaping wastes that might be dumped within reach of your horses. Besides toxic leaves from red maple and wild cherry trees, they may include highly hazardous trimmings, such as yew and oleander.
• Frosty nights make for dew-soaked morning pastures that can contribute to scratches on horses’ pasterns and “dew poisoning,” the painful puckering and cracking of the skin on the muzzle. Treat both conditions by gently but thoroughly cleaning the affected skin and, after drying, coating it with an anti-chapping agent, such as Desitin ointment.
• Many larger flies are killed off by the first frost, but smaller pests, such as gnats and horn flies, seem to go into a final frenzy of activity as cold approaches. Head shaking, eye and ear irritation, and crustiness along the belly midline are all signs of this last attack. Keep fly masks, ear covers and insectide protection going for a few more weeks.
• The return of cooler, wetter weather can produce a flush of lush pasture growth that could potentially trigger laminitis via an equine digestive tract long accustomed to parched forage. Keep at-risk horses off of regreening pastures or supply free-choice hay so they can take in gut-stabilizing roughage along with the succulent growth.