Is a spiky elm caterpillar poisonous to my dog? What are the signs?

Woolly Catapillars actually aren't toxic at all. They can cause irritation to the skin of some humans (and presumably dogs) with their hairs. My guess is that the vomiting is unrelated, but if it continues, definitely get Cruz to a vet ASAP for evaluation.

It appears the most common signs are often related to dogs licking or eating the catepillar. Below is from a 2012 study: "All dogs presented drooling, dysphagia (swallowing difficulty), submandibular lymphadenomegaly (swollen throat lymph nodes), and clinical signs of pain." Symptoms started in some dogs in less then 2 hours. Rapid vet intervention was important within 2 hours as some dogs had injury/damage to the tongue itself, especially if vet care was not sought right away. I hope this helps and thank you for using Petco Pet Education Center, formerly Petcoach!

While pine processionary caterpillars can affect dogs, a person with skin lesions would not be able to pass the irritation on to a dog. The caterpillar's hairs are what cause the rash and other symptoms so your dog would need to be in direct contact with the caterpillar to develop symptoms.

It is unlikely you will notice any trouble from one lick without ingesting it. Often times it will cause excessive drooling and you can try to wipe out his mouth ir rinse with water if you notice this

Not specifically--nettles are toxic mainly to livestock, and only certain species. However, any kind of pokey weed like a nettle has the potential to cause throat irritation after swallowing and I wouldn't be surprised if Bama starts hacking/gagging after ingestion. If this problem persists for longer than a dag or so, I would recommend taking her to your vet as she may need a medication to soothe her throat irritation.

The ASPCA recommends keeping your pet away from the pepper tree and the berries of the tree to be safe. They state that the tree can cause GI irritation, which may lead to vomiting, diarrhea, or a general appearance of feeling unwell in your dog.

I am sorry to hear about Jack! In the US there are no millipedes that are considered toxic to dogs but some may produce chemicals that could be distasteful or irritating to a dog's mouth. You can try wiping your dog's face/rinsing his mouth and offering some food to try to get the taste out of his mouth. If he begins vomiting or develops facial swelling/trouble breathing this could be a rare sign of an allergic reaction and he should see a vet right away.