Autumn is many dogs’ favourite season. The air is cool, the trails are quiet, and every walk smells like a new world. But the same season that makes walks pleasant also brings a quiet list of hazards: fallen acorns, wild mushrooms, rat poison stored for winter, and sweet-tasting antifreeze. Most autumn emergencies are preventable once you know where they hide. Here is a practical sweep of the risks that matter most.
Underfoot: Acorns, Conkers and Rotting Leaves
Acorns and conkers look like toys to a curious dog, but both are toxic. Acorns contain tannins (gallotannin), which can cause drooling, vomiting, diarrhoea and abdominal pain, and larger amounts can stress the liver and kidneys. Whole acorns can also cause intestinal blockages. Conkers contain aesculin and carry the same double risk of poisoning plus obstruction.
- Acorns and oak leaves: sweep the garden regularly; teach a reliable “leave it” cue.
- Rotten leaf piles: decomposing leaves can harbour mould, mycotoxins and bacteria, plus ticks and harvest mites.
- Fallen fruit: fermenting apples and plums can contain alcohol, and fruit stems and seeds add further risk.
Wild Mushrooms: Treat Every One as Off-Limits
Cool, damp autumn weather triggers a flush of mushrooms in lawns, parks and woodland. While most species are harmless, deadly ones such as the death cap grow in the same places and are nearly impossible to tell apart without expert help. Symptoms of serious mushroom poisoning can be delayed for six to twenty hours, which is exactly why waiting to “see how he seems” is so dangerous. The safe rule is simple: any wild mushroom eaten by your dog is a call-the-vet event, ideally with a photo or sample of the mushroom.
Garage and Garden Chemicals
As mice look for warm winter shelter, households stock up on rodenticides, and antifreeze appears in driveways as cars are winterised. Both are among the most lethal autumn hazards for dogs. The table below summarises the big three.
| Hazard | Why dogs get into it | What to do |
|---|---|---|
| Antifreeze (ethylene glycol) | Sweet taste; puddles under cars | Clean spills immediately; store sealed; suspected ingestion is an emergency vet visit |
| Rat and mouse poison | Grain-based baits smell tasty | Use tamper-proof stations your dog cannot reach; watch for poisoned rodents too |
| Mouldy food and compost | Strong smell in leaf piles and bins | Keep compost secured; rake leaf litter away from play areas |
Wiping paws after walks also helps remove grit, salt and chemical residue before your dog licks them off.
Dark Evenings, Fireworks and Fleas
Shorter days mean more walking in the dark. Use reflective leads, collars or hi-viz vests, and carry a small torch so drivers see you both. Firework season overlaps with autumn too; many dogs panic at the noise and bolt. Walk early, and build a quiet, safe retreat indoors with white noise or music. Finally, remember that central heating wakes up fleas: keep parasite prevention up to date through the winter.
If Your Dog Eats Something Suspicious
Do not wait for symptoms, and never induce vomiting unless your vet tells you to. Note what was eaten, roughly how much, and when. Bring a photo or a sample in a bag, and call your vet or an animal poison line straight away. With antifreeze, mushrooms and rodenticides in particular, hours genuinely matter, and dogs treated early have far better outcomes.
Autumn does not need to be a season of worry. A swept garden, a wiped-down dog, reflective gear and a short list of “absolutely not” items are enough to keep the fun in every cool-weather walk.