HI there, this is Dr. Elaine
You need to get her to a veterinarian immediately.
Call poison control: http://www.preventivevet.com/pet-poison-control
Some poison control numbers are free, others require a charge. The above link shows numbers for both (the Kansas University line is no charge)
It may be too late to make her vomit, and unsafe if she has been seizuring and has altered mental status.
However, a veterinarian can administer activated charcoal and give cathartic enemas after flushing out the stomach
, in order to prevent even further absorption of the toxin(s) in what she consumed.
Regardless of the toxin, the fact that it has made her seizure means this is an emergency. Anti seizure medication may also need to be administered by IV injection. Go now, do not wait any further.
The wax and sawdust in these logs can also cause an obstruction within the digestive tract, and some have heavy metals in them (zinc is one) that can cause seizures--there are antidotes for certain specific heavy metal poisonings.