The stem, leaves and blossoms of the Japanese cherry tree -- Prunus serrulata -- are toxic to dogs. They contain Cyanogenic glycosides, which is a toxin that prevents oxygen from being properly absorbed and transported by the cells. So, if you have a cherry tree in your yard, watch your dog carefully and rake up any blossoms, leaves or pieces of the tree that may fall off.
Signs of Ingestion
If your dog ingests the cherry blossoms, the reaction may be mild to moderate, but it will only take about 15 to 20 minutes after consumption to see the signs of cyanide poisoning. If your dog has consumed cherry blossoms, you may notice dilated pupils, difficulty breathing and bright red gums. Because it can be fatal, take your dog to the vet as soon as you notice that he's consumed any part of your Japanese cherry tree.